how to build ubuntu 20 or Fedora29 ?

Hi. I see google android builds from scratch (mostly?). It's online accessible by git. But unless running Android x86, which I can't get WIFI to work, I have to use Android VM. Preferred platform appears to be Ubuntu running Wayland non-X11 (is it X13?).

So to build the entire build chain my pre-built would need to include Ubuntu 20. What URL website explains that? Or what snap store has that how much does it cost? I guess 'apt' is now depreciated. Do I need docker or citrix?