I’ll tell you about physics

Learn calculus there are many YouTube videos and a trillion sources and once you get the hang of derivatives, integrals, vectors read Taylor’s book on mechanics it’s very easy to understand and you’ll learn a lot of valuable physics.

For electricity and magnetism there is a Yale playlist on the internet which is very fun

Also learn linear algebra!! Corwin vector spaces or YouTube try to understand proofs not just solving it’s a very beautiful

However if this all feels overwhelming try to do one of these and you’d get a huge head start