Spend some time learning how to install software using the terminal. It’ll be worth it, I promise.

Have you tried the collabora app for mobile?

I think Joplin has a spreadsheet plug-in.

No clue. Haven’t tried recently.

I spent about 6 months several years ago without a WM. I used links -g and gpm to browse graphically (and with a mouse) using the framebuffer. At the time, lynx couldn’t do that.

All modern OS’s require the terminal at some point (except iOS).

To your bonus question: portage