Windows key OEM (In bios etc) [closed]

Another pc has come my way, and it all boots and runs, I did a clean install of Win 10 and got an error for activation. After a bit of googling I think the Mobo never got activated maybe they used Linux on the unit, I don’t know the full history. I can extract a key with vbs script and Showkey has the same key and also states ‘No OEM key found in firmware’ The bit I find odd is a clean install of either win 10 or 11 both show the same key, with no internet connection, if the key is being generated as generic key from the usb sticks install software, why would I get the same key for both versions of os which are both from separate usb sticks, I would have expected a different key for both ? I did try the remove and add and rearm commands and re entered key but it ain’t activating.I guess I need a key!