This is a draw I got against a good player, with an greek gift sacrifice (Bxh7+) that probably shouldn't work, and a good ending of Knight and two pawns versus rook. I am unclear as to whether it is a draw or not. I am fairly sure that I missed a win earlier on in the game, but I suspect he probably did also.

In general, in greek gift sacrifices, after kg6 one plays qg4, not g4.  After 21. qg4 I believe you will have a continued attack, especially as 21. ... qxd6 loses a queen to the discovery.

26. e5 was a mistake as it opens the long diagonal to the black bishop, and your threat is very easily answered by 26. ... g6.  Instead, 26. rcd1 keeps the attack going, with the idea of a swift rook lift (such as rd5 or re1-e3-f3).  In that case I believe you are much better, whereas in the game you were worse.

The final position is indeed a draw, as black's pawns and king are too vulnerable, though he should have tried for a win given that white cannot win (KR vs KN is a draw in all but a few cases).  If the black pawns were connected, black would be winning.

Your one mistake was 21. g6. If you had played 21. Qg4! instead, you might have won this position. That is actually the main line of the Classical Bishop's Sacrifice.

thank you both. By the way, I am black, but the comments are good none the rest.

Oh, well then. That's good to know! Now you know how to execute the Classical Bishop Sacrifice when you need to, and how to respond to it when your opponent makes a mistake.