TL;DR: You want to teach yourself vim (the best text editor known to human kind) in the fastest way possible. This is my way of doing it. You start by learning the minimal to survive, then you integrate all the tricks slowly…
In my case, I learned enough Vim to be able to do quick editing on remote servers, it used to be that you could always find a Vi/Vim installed on a new Linux machine. Those days you can always find Nano installed on a new Linux machine so I mostly use Nano for quick editing. For serious dev work I use Visual Studio Code with the Remote Dev extension.