Is there a way to examine multiple games to find common errors


Yes and no. Yes, this feature exists. The chess.com Insights feature gives lots of statistics including how often you hang particular pieces, what your game accuracy is for various game shapes (sharp, intense, smooth etc.), times you missed checkmate in x number of moves etc. You can then click on them and replay those moments to help you improve.
The reason I say "no" to this is because this Insights feature only exists for chess.com Diamond members if I recall correctly. The good news is that there's a fan-made free version of this insights feature (which is basically the same thing).
I talked about this in the following video and there's a link to the free insights feature in my video description: