I’ll refer you to Welcome To Support And Help or the Start Here page, which states
Given your question appears to be wanting to get something to work with something else (that maybe a supported release), you’re welcome to ask about that, as that we maybe able to help with; but your question only mentions off-topic 20.04 specifically.
The oldest release in standard support is now Ubuntu 22.04 LTS, thus questions about 20.04 aren’t on-topic any longer.
FYI: Release notes go into some detail of the changes; but with focal or 20.04 being so many releases ago, you’re asking about a lot of ground; have you explored yourself (ie. read the release notes of later releases)