The game certainly has changed since Apple stopped using Intel chips in Macs in favor of their own ARM architecture chip. The expectation that a Mac runs the same Windows that you run on your Intel/AMD chip PC was thrown out the window.
There's no "upgrade" process for an installation of Windows x64 to Windows ARM. . You need to obtain the Windows 11 ARM installation media and do a fresh installation on Fusion 13 on a M1/M2 Mac. Existing Windows 11 retail licenses will activate Windows on both Intel and ARM chips. If you have a Windows 10 license it should also activate a Windows 11 installation on either x64 or ARM.
Take a look at the Unofficial Fusion 13 for Apple Silicon Companion Guide. It has procedures on how you can download Windows 11 ARM installation media (You can't go to Microsoft and download an installation ISO for Windows 11 ARM like you can for for Intel PCs).
- Paul (Technogeezer)
Editor of the Unofficial Fusion Companion Guides
