Fundamentals are nice, but rote learning of them is directly on the route to formulaic solving. You have to have something to force you to use math like an arti

Fundamentals are nice, but rote learning of them is directly on the route to formulaic solving. You have to have something to force you to use math like an artist and not like a computer. Which is to say, I highly suggest doing this stuff as long as you get value out of it. It'll be a boon to your comprehension speed later. Eventually, however, go find a hard textbook and work through every single line of it. Really. Understand that it'll possibly take years and involve finding many lesser sources to fill in the gaps, but without a hard motivating problem you're going to get stuck in an affective loop on formulaic knowledge. Easy, satisfying, but somewhat flat.