Master mathematician here. I'm giving you advice on how to be good at mathematics.

1. You might have this emotion inside you that mathematics is BIG subject. It's not. Stop thinking it as BIG. Rather think it as LONG. It's very long, but extremely flat and overwhelming majority of branches your brain might make wont lead you anywhere. It's not like roots of a tree. It's like long piece of rope and occasionally some of the rope strands fray from the main body. There is usually one type of freedom in math and it is FORWARD or BACKWARD.

2. You might think that solving mathematical equations is hard. No. You can solve a problem if you have done similar problems before. That's how mathematics works. Your job is to progress from simpler problems forward. Like building a pyramid. You can solve a problem ABC if you have solved the problems A B and C before. If you cant solve ABC, intensively focus and search for problems like A, B, and C first.

3. You might think that thinking gets you far in math. Thinking doesnt progress you much. Mostly what you need to do is move the subjects into your working memory, fill your working memory with mathematics thing, then forget all about it and go to sleep or eat or whatever. Fill your working memory. Then stop. Then return. Do this every week. You have to do it a lot, maybe 30 hours a week. That is a lot of mathematics.

4. You will get good in mathematics if you ALSO seek for motivation to do it. Seek to get rewarded. Use 20% of your time to seek rewards you can obtain with mathematics.

5. Best way to learn is friends and competing against them.