First of, I am not looking for direct help, like someone doing it with me, I can do the whole thing by myself. Its more of a where do I put this kinda thing.
So I have changed a lot of things on the https://github.com/Regalis11/scpcb but where do I put the file in the SCP folder?
Oh and where do I change the text in the menu and death screen and the files (in game file of said SCP, e.g. SCP-173 file), I can't seem to figure that bit out?

If you are looking to change the code, download Blitz3D and Notepad++ (it's what I use for programming). There is a post explaing on what to do, not by me though.

Join third subvisions discord head to modding tutorials there is all the software you need