https://kb.parallels.com/en/124294
KB Parallels: Unable to use BootCamp based virtual machine after upgrading to macOS 10.13
Cannot create a new BootCamp based virtual machine or launch the existing one after macOS 10.13 upgrade.
kb parallels unableusebased
https://forum.parallels.com/forums/macos-virtual-machine.115/
macOS Virtual Machine | Parallels Forums
Share your experience about running Mac OS X in Parallels Desktop.
macos virtual machineforums
https://kb.parallels.com/125561
KB Parallels: Install macOS virtual machine on a Mac with Apple silicon
kb parallels installmacos