If you want a to get this stuff into your head reasonably fast, go implement a curve. Then do it again, but in Rust (or C) and in constant-time. Then do it again, but actually computationally efficiently (i.e. optimize the hell out of a Rust or C implementation once it works). Choose a different curve each time. Then go and cook your own curve for shits and giggles.

You may easily spend a year upwards on this, but by the time you're done, you've basically run into every resource worth knowing about and are able to decently reason about elliptic curves (but by no means are in a position to write papers still).