I wasn't unhappy for a while but then it all started going wronger and wronger.

I'm most interested in the general situation right before and and, if it wasn't bad, where should those moves have been played.

{insert caveats about not being stronger than you here}

move 30 seems like trouble to me. You put a great deal of effort into keeping blacks groups in that corner separated and attacking the more central one, but then you let him connect. Perhaps R2 instead? I do see the concern about the Q6 stones not being surrounded, but it seems like if black pushes at R7 you can attack his three corner stones, and if he plays at R6 or R7 you can connect out at Q7.

move 36 is clever sabaki play, or a mistake.

move 70 seems questionable to me, jumping into the premade pincer. In that position, jumping out at F15 feel more natural. E10 gives a nice target for escaping towards, and you can simultaneously threaten the corner and the H17 stone, especially given that moves right of H17 can threaten both H17 and the top right black group. move 70 seems to concede a lot of influence to black, whose already strong in that department. A good escape could go a long way to counteracting his thickness.

On a large scale, I think it went wrong at 15. That move affected the flow of the game through to the end.

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A beginner question here if you don't mind. I'm looking at the final board position for this game when white resigned. Is this game really beyond saving for white? Or is it considered rude for white to continue playing from a losing position since black is ranked higher?

I'm just trying to get a feel for the etiquette of when to resign. I know not to struggle futilely. But as a beginner, if my board looked like it does here at move 104 (not that it would), I wouldn't have thought the outcome certain. But I guess I'll get a better feel for that as I play.

White may have been a bit premature to resign, but not by much, for the game definitely favors black.

The secure points are roughly equal at about 50 points each.

But white's string of stones from G5 to E10 are in serious trouble. If black captures them, not only is it 18 points for dead stones plus the intesections that they occupy, but it is closer to 50 points for black when he takes much of the center. The best that white can hope for in his own column is to take an additional 30 points on the right side - and that is only if he plays first, preventing black from playing R11 or R12.

So white looks at the future possibilities, sees that he is probably down by 20 ( 50 - 30 ) and resigns.

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Some comments on the early play.

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Visualize whirled peas.

Everything with love. Stay safe.

Thanks for the explanation Joaz. I was thinking that white's G5 - E10 string could maybe survive by running out to the center and reducing black influence at the same time. But it sounds like that's an unlikely scenario.

Considering whether or not it's rude to continue to play, In my opinion, if you think you can save those stones you should try.

That way you get a better grasp of what stones can be saved and what stones are too deep in enemy influence.

Also you see what black gains if you try to run away with these stones.

I agree with the other answers about reading the game as being quite favorable for b, but I'd like to add that the rank difference was an important reason.

Whenever a stronger opponent accepts an even game with me I take it as a gift and I pay special attention to not forcing him to keep playing if it gets boring.

Against someone my rank I'd have tried saving those stones at least until I was able to read how to kill them if I were black (so half a dozen moves or so I imagine).