Can someone please explain me some moves from my game?

Hi there, this will be a bit different because I didn't know games can be shared all along with moves while I was playing, so I took a screenshot of my game and was writing following moves in notepad. However, I don't need analysis as I am like 500 ELO, I am very bad at chess and I was literally playing vs Computer 400. However this should be easy to understand for someone who plays chess I guess, I am basically curious about one move, you can disregard the rest as I know they are wrong.

I kind of didn't have a good idea here, but Pawn c5 seemed like a good option so I played it and was about to ask on forums what was the best move but ended up finding nextchessmove.com and according to Stockfish 15.1 i was right. However I analized the moves that followed and they were wrong.
Black plays Pawn e5
Queen a5
King e7
Pawn eats d6
King e6 (According to Stockfish, I should have played King b1 after this but I played Knight a7, can someone please explain to me why wasn't my move good if it wasn't?
Black plays Queen b7
Queen eats a6
Queen eats a6
Bishop eats a6
Knight g5
Pawn c8 > Queen
Knight f7
Queen a8
Pawn h5
Bishop c4 checkmate

Thank you in advance, I would really like to improve in chess because I love it, my friend plays like crazy but he lives in different country now so there was nobody to ask.