Someone on Mastadon pointed me to this helpful page https://eclecticlight.co/virtualisation-on-apple-silicon/ and I successfully got a VM running! However I can't sign in to the App Store. No matter what I try it tells me in red "The action could not be completed."

I learned about the limitation elsewhere. What a shame, but it makes sense that Apple would not want to encourage anyone to test or support older Operating Systems. Thanks for taking the time to reply!

Ok thank you.