Still can't get NC installed

A manual installation like this shouldn’t cause so much trouble, so I hesitate to suggest an alternative to you. You could try running the snap package, which is almost entirely hands-free on setup, but be forewarned that it’s rather inflexible.

If you want to try Docker, I wrote a guide for that. I prefer Docker personally because no matter your *nix flavor or what else is going on with your system, the Docker container comes with its own stuff in a stable and known-good setup.