1. Autistically go through all these foundational and proof books that spoonfeed you?
or
2. Go through problem books that don't hold your hand first (Challenging Problems series, Putnam and IMO), not checking solutions until you've tried your absolute hardest?

or both?

I feel like the former is like systematically learning a language by rote memorization and grammar drills, while the latter is like actuallt travelling to a country and learning the people's language purely through conversation and experience.