When running the Windows IS in a VM it consumes a lot of CPU resource because of Microsoft's Defender Antivirus. Especially when updating applications or using external disk resources through Samba.
Run a elevated powershell and run the command:
Set-MpPreference -DisableRealtimeMonitoring $true
This method is only available for Windows 10/11 Pro, Enterprise, and Education editions.
Open Group Policy Editor:
gpedit.msc
Navigate to Windows Defender Settings:
Go to Computer Configuration > Administrative Templates > Windows Components > Microsoft Defender Antivirus an disable Microsoft Defender Antivirus.
Double-click on Turn off Microsoft Defender Antivirus.
Select Enabled and click Apply, then OK.
Reboot the system.