Step-by-step explanation:
Modeling is the idea that after a child watches something they are more inclined to do it and Mirror neurons essentially do the same thing (in the brain where if we see something the same neurons will fire when we actually perform the task.)
The process of the Bobo doll experiment was that children would watch an adult beat up a Bobo doll, Then when either released into the room to play or given a frustrating situation, They would model the behavior shown previously and also beat up the Bobo doll.
This can be translated into playing violent video games in the same way as watching someone else (in this case a character in a video Game) Would theoretically lead players towards more violent behaviors.
hope this helps :)