First and foremost, Nitrux makes use of snap packages; so installing software is handled a bit differently than the norm. Even though Nitrux is based on Ubuntu, apt install isn’t what you want to use (although it is available).
I’m getting ahead of myself. This distro focuses very much on the GUI — so the GUI should be the route you take. Good thing Nitrux includes a GUI software installer tool for that purpose. That Nitrux uses snaps is good and bad, and it’s the bad that will put users off faster than the good.