Hi. Welcome to the THGaming Community. If you're on a Windows computer you can open the screen recorder by pressing [Windows Key] + [G]. This opens the 'game bar' menu which has options to record video. You might need a decent graphics card to do this as some of the older cards don't support screen recording on Windows.
I also googled how to do this : "Press the Windows key + G to open the Game Bar above your game, application, or desktop."
!PGM
!PIMP
Upvoted :)