windows 10 activation errors

I am a rookie to dual system between Mac and windows system I installed my parallel 18 desktop and windows 11 But I need Windows 10 to keep my racing wheel driver work. I setup Windows 10 OS but the wrong message appeared. It failed to degraded from windows 11 to windows 10. How could I do step...

The ARM .vhdx file Parallels recommends we download installs Windows 10 Pro - do we have to buy a license to activate this or will a Windows 10 Home version be available soon so we can transfer product key?

Installed Windows 10 Pro on Bootcamp - went well - FYI - Macbook Pro 2018 MAC OS 10.13.6 I installed Parallels on top and went well - but now I am getting "Windows needs activation" again and that it this key is "already used on another computer" - Had to get on phone with MS technician to get...