How to make multiplayer to work?

Me and a friend of my is working on a intense game of pong. But we are strugging on how to make multiplayer work. Problem is we can’t get to control the left pong, here’s how we attempt to do it.

Screenshot 2020-07-04 at 12.56.18 PM

Screenshot 2020-07-04 at 12.58.08 PM

Anyone who is good at multiplayer, please help us find the slove!

Make sure that the player count is 2 or more and that all the program has different buttons to activate