Registering and patching Ubuntu (20.04) with Foreman/Katello

Every tutorial I have found and followed lays out steps to create a CentOS product and repos with upstream URLs such sa

Is it possible to register and patch an Ubuntu host and if so - how?

You can find information about managing Ubuntu systems inside the orcharhino documentation.
Please note that orcharhino like Satellite6 is a commercially supported downstream product of Foreman and Katello.