Vim has become my go to te editor; though I'm laughably "bad" at it. (e.g. I still use the arrow keys, etc) — I suppose this could be a bit of encouragement, don't worry too much about being hardcore, you can actually have a go at it "incrementally."
Spoiler: you quit with ESC and then
to leave without saving or
to save ☺
Reddit thread with lots of links to Vim-like tools.