Help with improvement

Hello, I'm looking to improve my chess game and I need some help figuring out some of my misses and blunders. I won the game, but my moves 11, 13, and 21 really confuse me and I feel like I missed a tactic can someone help me understand this position better and give me some direction? Also, I noticed whites 23rd move on move 21 or 22 and I kept trying to push my ideas on the other side of the board. The engine said it was a blunder for white and I can't see that either.