Question on what this person is talking about. (Noob)

For context i made a remark that a good %80 of games that work well on windows don't work on mac at all without using some third party sources. Now the person is talking about editing the efi folder to allow some extensions, my question here is what kind of extensions you can put into the EFI to change what exactly? All I could find online is that the EFI is primarily used for firmware updates or that it contains data on how the boot process should work. Other than that all I can find is just hackintosh stuff related to the EFI. What can of changes or extensions I can put in the EFI for my mac?