First of all, you must make sure that you are a very motivated student. In my opinion, there is something wrong with your study method. Junior high school mathematics is very simple. Don't improve your grades by doing a lot of exercises (unless you take part in the competition). You just have to read your book carefully and do the exercises at the back of the book several times, and you will be familiar with it. Do it a few times more. You haven't settled down. You can do the basic questions in the book first, and the exam is basically ok. Besides, you are too young to think about work. Read the math book carefully and do the exercises in the book. I used to be like this.