that's a question about learning resources for those of you who studied any of these (yes, i know they're very different).

I come from the bio and chemistry side of science, so know absolutely nothing, except some high school level math. I need an organized free online course, with ways to practice and to measure my progress. youtube videos and khan academy-like sites don't have any exercises.
the best course would get me to high-school AP level. anything better than that is a bonus.