move old software to new but same Ubuntu install

I was almost finished with configuring Ubuntu 20.04 (two days) when the screen went dark and I could not get a good reboot. Unable to fix it, I installed 20.04 on a different hard drive. The linux version on the old system (left unchanged) is newer than the more recent install: new is 5.8.0-38-generic, old is 5.8.0-58-generic. I want to move all my changes to the old install to the new without having to make the individual changes again.

Thank you,