Question / Help New to OBS and need help setting up

[GhostTurtle212]

So, my main problem is that I can't get OBS to show my game screen, or even acknowledge that there is a game screen. I'vs seen a couple Youtube videos, and they just aren't having the problem. I'm trying this on a MacBook Pro with the most up-to-date update, and the newest OBS. Could I please get help