It's super easy. The sad part is all the kids who don't realize how easy it is and get convinced that they're stupid or that they're not math people.

Math in which you require to be able to handle increasingly abstract ideas doesnt really come into play until you're well into your university studies.

Anyway start here, and if youre doing good and are ahead try helping some of your classmates that are struggling and are left behind by not treating it as you having some special magical ability but as something that anyone can do. This attitude will take you much much farther in life than one of being exceptional or special.

https://m.youtube.com/c/ProfessorLeonard

This is all you'll ever need. And a textbook he uses Tan, which is easy enough to find. If you find calculus 1 hard start with his precalc lectures.

Khan academy is also good.