The article
https://kb.parallels.com/en/129871#section5 says the following under the section
Setting up automatically:
To install it, open Control Center in Parallels Desktop > create a new virtual machine from the list of Free Systems and select Download Ubuntu with x86_64 emulation > click Continue to create and start the virtual machine.
But there is no "Download Ubuntu with x86_64 emulation" system in the "Create New" window, only "Download Ubuntu Linux". I'm running Parallels version 19.1.0 (54729) on a 2021 M1 Max MacBook Pro, macOS version 13.6.1 (22G313).