I'm a junior high school teacher, and I'm also a sophomore this year. Of course, the main reason is that my daughter is also in Grade Two. Otherwise, I should go with the class and go to the third grade. (You can check my profile)
As for math and physics, you can see from your words that you really want to learn these two courses well. However, due to various reasons, the results of these two subjects are not ideal. This is actually a very normal phenomenon. People are not omnipotent. If they have strengths, they will have weaknesses. What you need to do now is simple:
First of all, no matter what else, no matter how annoying, we must stick to it, starting with the simplest basic questions and exercises after the book. Don't be afraid of simplicity and trouble, lay a good foundation first. Don't do too much exercise in the exercise book, it has no substantive effect on you, just wasting time.
Second, learn to ask more questions. Ask not only the teacher but also the classmates. Keep a low profile. Doesn't mean no, no. I can ask, there is nothing shameful about it. On the contrary, people who don't pretend to understand are the most shameful. Being able to keep asking questions can solve your problems as soon as possible, save your time and increase your confidence in learning.
Finally, I tell you an unfortunate news. At least in junior high school, you have to study math and physics. Even in high school, mathematics is a compulsory subject in both liberal arts and science. So, listen to a suggestion, don't think too much about other things, and concentrate on learning it well. Perhaps, in the near future, you will find that these two subjects are not very difficult!
All right, that's it. I'm not very proficient in physics. In mathematics, you can ask me questions. My daughter is as old as you, and she will be in the third day of next semester. For mathematics, you can ask me, please contact me, or you can check my personal information, which is all in QQ. I wish you a smooth study and a happy holiday!