Yeeep. Best thing I ever did was figure out how to learn on my own. Very few people are simply handed a proper education, even in good ol’ rich USA.
It’s hard as hell, and you NEED to learn to kick yourself (at least if you’re stubborn like me) and realize when you’re plain wrong. I think that’s the biggest hurdle most have: grapling with the fact that they don’t know what they’re talking about.
Other than that, it’s al heuristics: What do you know that might connect to something else you need to know? Then strengthen those connections until you’re studying the direct topic some day.