Accessing local file system for a Unity remake-mod

I’d like to make a remake-mod for a game using Unity. The game runs on Windows only. Obviously read/write access of the host game files is required. What’s the best approach, if even possible, to access files from a specific folder?

Edit: found this Accessing Local Computer Files.
According to @Bunny83 normal System.IO access is possible in Unity, at least for Windows. Can someone confirm this? And is there any protocol to follow or can System.IO be used directly? Why is this topic so poorly documented btw? I can barely find anything about it.

This is going to be highly dependent on the game you’re attempting a remake of. I would start by looking around the web and see if there are any tools out there specific for this game to edit/view resources if you aren’t trying to remake those from scratch as well.

For example, if you were wanting to do a remake of Quake 2 you would use something like this to extract the models.

Then find a way to convert them to a format usable by unity.

Best of luck!