I am white! Thanks in advance

I think you played much better than the 13k that is showing up next to your handle. Overall, I think in this game maybe your attacks went after small targets rather than larger ones, and so perhaps you underestimated how much your opponent can get by sacrificing small numbers of stones.

I agree with CC, and I would take it even further and say that you may have attacked when you should not have attacked at all.

In particular, at move 28, his group has little effect on the rest of the board. It has very little future. It cannot expand significantly to either side. It can expand to the center but with very small profit for the moves expended.
It can't attack to the left for you are too strong on the left. It can't attack on the right, for doing so would force you to secure the corner while defending yourself.

Having it there, and having it slightly weak actually benefits you. It almost guarantees that the corner will be yours without you having to occupy it anytime soon.
If he invades the corner, your replies to his invasion will make your lower right group strong enough that you may be able to kill him and take a big chunk on the lower side.

At 28, I would tenuki. Let him worry about his weak group. Let it complicate every decision that he makes anywhere near it. Let him waste another move trying to guarantee its safety.

While he does that, you make big moves elsewhere.

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Thanks for the advice!

Thanks!