Senior high schools should hold competitions, read more books about competitions and expand them appropriately. College textbooks need a lot of calculus knowledge. It will be difficult if you don't have enough math, but in fact, you won't use so much math in the competition. Feynman's book is very good, but it is not suitable for beginners. Need a lot of foundation, in other words, basically need a general physics course in the university, which is not helpful for the competition. There is also the theory of relativity, which is more difficult, but it is not the focus of the game. I suggest you finally tackle the problem and start with thermoelectric.