To get the computer analysis here, I think you have to analyze games played on chess.com.
However, I think that the computer analysis is one of the weakest features of chess.com. As a premium member, it's a little stronger (it says 2500 level ELO), but it's still much weaker than most of the engines out now. (which are running above 3000 ELO).
You should get and download a free engine like Stockfish using a free GUI like Arena. They will analyze any pgn file on demand. You can limit the time search if you want it to look at a whole game or have it search on one position until the cows come home.
I have tried many software but many of them cost a lot especially since I am paying preminum membership on Chess.com. Is there a feature where I can use Chess.com to anaylze chess games? Thanks!