Question very specific problem with bootcamp/graphics drivers

Oct 5, 2022
so my friend has recently got a new iMac with windows 10 installed on it through BootCamp, but recently, mostly in games, he's getting tons of ghraphics driver errors. now I'm typically the one my friends go to with PC issues, but this one i just cant figure out. whoever he bought the system from has somehow completely removed the MacOS drive, and removed all of the BootCamp assistant files on windows, making it impossible to get the drivers through there. i feel like we've tried every solution under the sun but just don't know what to do.

ill give some of the specifics of his system,

processor: Intel Core i7-2600 @ 3.4ghz

graphics (according to his device manager): AMD Radeon HD 6900M

OS: windows 10

any help would be great, thank you