Understanding why the "better" move is ultimately better

Since started using chess.com a lore more a few days ago, as I purchased a chessnut to connect to it,  After each game with an opponent I run the analyses and I always look to see what after a game I review the analyses and Chess.com [stockfish or komodo] analyses engine suggests as what would have been the "better" move.  Often times I see why, but many times I stare and stare and I am not sure why the engine determined the better move.  I see underneath there are a lot of chess move notations. Is it possible for someone to explain how I should use the notations for the better moves to understand ultimately why the engine proposed the "better" move?

Thank you!

Thank you so much?