I don’t want to get too deep into technical jargon (because I don’t know any) but I think the problem was when you lost all your pieces.

Your mistake was taking their king, that makes it so you can’t checkmate them anymore.

Antichess, the truly anarchic variant, where en passant is really forced

ah yes a classic stalemate position

puzzles, going to a chess club with trainers that can teach you

Try to play as both players. Don’t move until you’ve decided what your move is going to be, but also what you would do next if you were the other player too.

Then move.