Need to restore System 32 folder to original state, anyone know how?

Many programs don't function due to my past fiddling with said folder trying to get the Witcher 3 to run. I've tried sfc/scannow but it never detects any issues, but when I run many games (Rising Storm 2, PUBG, The Witcher 3) they either don't start at all or give error messages saying files (Which I do not recall interacting with) are missing from the folder.

Would anyone be able to help me figure out how to revert the system32 folder back to it's original state? Thanks in advance.