I'll be honest, I'm not sure what you want here. Might just be tired but I legit cannot understand what you're asking.
If you're looking for an easier way to learn than reading the docs the plugin which-key is good at that.
As for a right click menu, sorry, I can't help there. I haven't seen any good plugin for that yet.
Edit: Maybe this for right click menu?
https://github.com/meznaric/conmenu
As for general menu for settings you're not going to get that here. Sorry about that. It'd be a cool thing to see though I'm not at all against such a plugin existing. Not sure I'd use it personally though.
Wish you the best nonetheless. If you're unable find what you want in vim BTW, maybe try out EMACS. They tend to be more pro-gui there. I do sincerly hope nvim works out for you though