I think category theory will give you an unique point of view of math, also basic logic and philosophy are very important for a good and solid foundation on math intuition.
https://arxiv.org/abs/1803.05316 along with their youtube lectures.
very basic but refreshing:
https://www.youtube.com/playlist?list=PL8dPuuaLjXtNgK6MZucdY...
if you are a programmer or developer:
https://bartoszmilewski.com/2014/10/28/category-theory-for-p... https://blog.ploeh.dk/2017/10/04/from-design-patterns-to-cat...