Update: I was advised to use the Gnome Software app (GSA) for this. Which makes sense. I was actually able to find the file I was looking for this way, just under a different name: jack 2.
The truth is that GSA handles all the things I had mentioned before: Finding, installing, uninstalling, etc.
I like the Terminal, do not get me wrong. But I don’t always have the command-lines need at the top of my head. Sure I can always do a search for them, but then that’s another task to add to the list. With Synaptic I could search for a file I needed (like libjack0 now). And not only would it find it but it would also offer to download dependent files. Install them where ever they need to go. And to remove them I can go back to it too. It would be nice to have one.
I understand CL doesn’t use APT, but doesn’t it use something else to do the same (more or less)? If so, then does it have a GUI?