It will definitely have an impact, because mathematics is a highly coherent subject, and the knowledge of high school will be based on the knowledge of junior high school. If you don't learn the knowledge of junior high school well, you may get the knowledge of senior high school somehow. In fact, when studying mathematics, you can refer to the answers I gave to other students, hoping to help you.

The fastest and most effective way:

First, read the textbook, first understand the concepts, theorems and formulas, and make these things clear.

Second, look at the textbook, how to solve problems with examples in the book, and learn the direction of solving problems with examples. In other words, if you encounter the same problem, how should you think about the direction of solving the problem, that is, which direction should you learn to achieve your goal? This is the most important thing, you must learn it. This is the basis of learning mathematics. The direction of learning to solve problems is that you have wisdom and learn concepts, but learning knowledge and wisdom is the most important thing.

Third, there are still some problems to be done, but they are not sea tactics. Learn to sum up, that is, which direction to consider when encountering such problems. What conditions does this question give? What formula do you want to use when you give these conditions? Generally speaking, conditions must be exhausted, but they will not be insufficient. This is a principle. It is ok to learn these when you do the problem. I wish you good grades.