I really can't recommend Drew Neil's resources enough. The vimcasts¹ series are great if you're the sort of person who likes videos to learn with, and both his books are excellent²³. [The books may appear to be getting a little long in the tooth, but their contents are still very applicable to today's usage.]
My own "trick" for improving my vim usage was to start mapping things to <Nop> that have better replacements, it is a great way to shock yourself out of bad habits like hjkl movements or reliance on /. Then again, I think text-objects and the items below it in motion.txt are the main to use vim so YMMV.
² https://pragprog.com/titles/dnvim2/practical-vim-second-edit...