Oof! Tough game!
I think maybe before I played 10-8 it's possible that the bots would say I had a lead? (they would probably be a lot more confident about dealing with the centre potential, against a stronger opponent I would expect it was comfortable enough for black)
I think 10-8 was slack and then each move since has been loosing both points and aji.
Black's bottom left group is connected through and can live anytime by extending into the corner. However since it's not 2 eyed I think I need to lean hard on it in an attempt to try to do more at once. Expecting a squeeze here but I'm not confident black won't respond differently.

Poke.
Knight's move.

Well. I wanted to play 8-6, and capture this stone in a ladder. But I actually think I might be killing myself by doing that - when he squeezes my three stones I would lose some critical aji in the center. I'm actually using my two dead stones at 11-5, 11-6 to make my last forcing move for the second eye in some variations. So I think I need to make this exchange first, and then I think I should have enough aji on the side to make my second eye. After that I can come back to play 8-6 and save my three stones.

Of course, this is offering a trade where he can ignore me to take my center three stones. He could then continue to try to attack my bottom left group. But that just seems like it won't be too profitable for white, when my followup cut on the right is not only capturing 20ish points and securing my group but also threatening atari on his right side ponnuki.

I'm somewhat suspicious of his evaluation of this game. It doesn't feel like he's aiming for a squeeze on my three stones to go back and attack my bottom right. It feels more like he's trying to tenuki and he thinks this cut is the proper followup in the center. I don't think that that's true, but maybe it is just a technique to aim for the squeeze? Maybe I have another ghost stone floating around, whatever it was that made him play 10-8.

Its great advice that after a mojor blunder you should stop and regroup and beware making another. My last move was a bit slack. The right hand side isn't done yet.

On the plus side black has forced me to play a move I kind of waned to play.

Atari.
Connect.
This move was frustrating. Let me talk through my reading. Here's the threat:

What if he starts at 15-8, I block at 14-8, and he protects at 16-9? I'd have to protect the cut with a move at 13-7, but then he can try to cut me off from my middle stones by playing at 13-10. I really want to be able to make two eyes or connect from that position. If I push at 13-11, he might push at 14-10, letting me continue at 14-11, and then connect back his two stone with something like 13-9. I'd have two cuts to worry about, 15-9 and 15-11. 15-9 pretty much has to be defended instantly with by playing at 15-9, which happens to be atari. Then he can cut at 15-11. Remember that this cut is supported by his old knight's move at 15-12, so I can't ladder it or anything. It looks like the best variation for both sides is just for me to capture the stone, and him to make a ko for my two eyes. So unless I can find better moves to play, I'm currently only alive in ko.

The move I was incorrectly eyeing up behind my last comment is 17-9 first in response to 13-10. The problem is that he can play 17-8 and demand that we still play a ko.

But why am I only now suddenly worried about this, when before I couldn't find a way for him to kill me? Well, what if I play 12-9 in response to his 13-10, trying to break out on the bottom? He pushes at 13-9, I turn with 13-8, and he saves his stones to stop my from connecting with either 13-11 or 12-10 (or maybe 11-9). Then I should atari his 12-8 stone at 12-7, threatening to connect to my three stones. The key here is that I can atari his two stones at 11-6, 12-6 because I still have my two dead stones at 11-5, and 12-5. So this way works! This is the variation in response to his 16-9 tiger's mouth attack that I had prepared assuming he was trying to kill me outright.

The problem is that it stops working when he squeezes my three stones in the center, because he gets the move at 11-7 in sente.

Do I think that he sees that the cut on the left that he's playing is currently threatening a ko on my bottom right group? Frankly, no. I'm not sure that my reading is correct either, since I could easily have ghosted a stone in one of my variations by accident. But I should play as if I'm correct, and he knows too. It's incredibly frustrating to have to admit that your opponent just made a really good move, especially when you think it probably wasn't completely read out. It's just how it goes sometimes, I suppose.

So how to defend? It's really awkward, since no move nearby is close to as big as the left. I guess I'm playing the central atari, since the take will be my sente and I'll have a lot less central aji to worry about. But the game is definitely good for him again.

Yep. I was just looking at how that elephant eye looked a bit shifty for black. I think my last move fixed a weakness to make it work so black had to do something like that to fix up.
(not a great time to write up example sequences now but may add later)

It's tempting to play again in the centre so that I'm safe and maybe blacks lower left group can be mildly poked about but I have the opportunity to take more than my earlier counted 24 points here and to fix up so I can't be harrased further.

Push.
Connect.

Between this and 14-8, I prefer this one, since it exposes an extra weakness and is good local shape. 15-10 itself is not heavy and I shouldn't treat it as if it is (not that he can push up immediately anyways).

I guess this might be considered a good exchange for white, but he really ought to get back to his 8-7 stone. It's not as good to make exchanges when there's a threat looming, because your exchanges lose the ability to threaten to take a big gote. Also, I just defended this area, so in general I'm thicker than I used to be here - if he wanted Q9 he should have played it before I defended. Even up into the mid-dans people make this mistake, where their eye follows their opponents last move and they unintentionally justify it. When your opponent adequately defends themselves, you should generally look to play elsewhere, and not follow it up.

I should have taken that 15-8 point before pushing through here. I'm not paying enough attention to this game at the moment. I guess that might have harmed my centre group slightly though

Cut.
Double atari.

Um. I just said he couldn't take gote. Well, looks like he gets the right side, and I get everything I wanted. I'll take it! I briefly considered making an exchange on the right, but nothing looks good enough to do before the important thing.
I double checked the ladder just to make sure I wasn't hallucinating

I've got no idea what he's going to do next.

For a moment I was going to give up these two stones and just atari, but I get a kind of squeeze anyway like this and I keep black with one and a half eyes this way.
If I can get 3-2 in sente by keeping this group eyeless then that would be nice.

Ladder.

My god will this be embarrassing if I somehow misread the ladder for the last 70 moves. But I don't think so

9(J)-10

I could atari the 3 stones to live right away, but I want to be more active and try to spoil the centre a little bit.

Captures.
He jumps.

Hane.
Captures.

Everyone is always like oh man, I gotta respond and keep my moyo. Nah. That's not how you use the stone effectively. Right now, he's jumping into my potential territory - directly, his move made 0 points. My move made 20 points. This is how you catch up to all those early territory moves before they know what hit them.

Okay, it's not that simple, since you can't just tenuki to every reduction on a moyo - I had to respond earlier on the right, for example. The way you check is by calculating the difference in size after a black first move followed by some white sente, as opposed to a white first move (and maybe some more white sente).
If I play first, I'd play around 9-12. He could then attach at 8-12, I hane, he extends, and for the sake of argument suppose I protect. That looks pretty settled, so I hold that position in my head.
If he plays first he'll play maybe 8-12 again, and then I can play 9-13, he'd play 8-13 and I'd play 9-14. That looks close enough to settled to serve as a good comparison.
So how many points different are they? Around 8. The difference in strength nearby also has to be taken into account, but in this position that strength is not very useful. I think it's fair to call it a 15 point move, but that's too small in comparison to about 20 points on the top.

Anyway, now that I've captured the ladder stone I feel more comfortable down on the bottom left. The reason the three stones were big wasn't really because of territory or because he's attackable, but because it brings me out. He's right that if he tried to play the last forcing move right now, I wouldn't respond. Since the ladder aji is clear I don't have to count extra nonsense points for him on the left, which is nice. With his last move, he's made 8-9 a shape point, but I don't want to take it yet because it lets him jump much further into my moyo on the top. If he plays it, I'm happy to make a move towards the left. I considered playing that move immediately with something like 4-8, trying to establish something on the left and slightly pressure his corner. But it's really just not as good as the big fat dinner of points on the top.

I figure I should count again now that things have calmed down. My expectation is that I'm still slightly behind.
For B: Bottom right - 2. Bottom left - Assuming he gets the hane under in sente, I still have some work to do to live. Call it 5 points. Top: 8 points in captured stones, 35ish in the moyo. Total: 50ish points.
For W: Bottom left - 10, top left - 8, bottom group - 6ish, right side - 30ish points, plus komi - Total: 65ish points.

So I've caught up a bit, but not as much as I thought. Maybe my extra defense on the right should have been on the side instead of in the center, though I think that had some problems as well. Well, I have to hope for a decent result on the left side and good endgame, I suppose.

Seems good timing for that endgame :/

I think I shouldn't leave it too late to squeeze with 3-19. Since this top right corner could be a ko, I'll play it first so I have one extra ko threat... I think that's sound logic.. Not sure

Atari.
Ko.

I realized during our count of captures that I forgot to add captures into my count, so I'm only about a dozen points down.

I also have to admit, however embarrassing it might be, that I still can't figure out where I got a 4th capture

Anyway, since I'm still behind, and there's a decreasing number of unsettled areas, I should add complexity to the game. Making ko here can only be losing a little bit of equity, and the game probably becomes harder to handle for him. I have a bunch of ko threats in the bottom right, while his right side ko threats look really loss. I also have a bunch of threats on the upper left, though he does have some extra threats due to my just taking the four stones.

My real plan, though, is to use 3-8 as a ko threat. It looks really hard for him to answer. If I make other ko threats first, then I'm mostly just hoping he'll make some bad ko threats before I get there.

What I would do if I were him is just ignore the upper right entirely and start playing normal moves until white has more ko threats than black. I'd be forced to keep considering the ko situation, and he might be able to do a slightly better late middlegame than otherwise. Basically, I'm suggesting 4-9 for his next move. I'd be feeling real rough.