PlayOnLinux is a graphical front end interface for Wine. And if you don't know already, Wine is popular software that allows many Windows applications to run on a Linux system. The problem with Wine is that you sometimes have to do quite a bit of configuration to get a particular application to run; we even have quite a few guides about it on this site.
This is a companion discussion topic for the original entry at https://linuxconfig.org/how-to-install-playonlinux-on-ubuntu-20-04-focal-fossa-linux