Being jealous will not solve any problem. I would say for mathematics you will need to practice and know the practice really well. I would recommend you to at first understand the concepts. Do the derivations and understand how the formulae are coming. If you understand the fundamental procedure of problem solving then you will be able to solve problem in the subject. To build your confidence , solve the problems in the examples without seeing the solution. With time you will gradually feel confident and you will be able to solve maths problem as well.

Also give some tests. You may give test if you have home tutor or coaching classes or you can just practice the previous year questions in order to improve time management as well as knowing the type of questions.

I hope my answer helps. All the very best for your future endeavors!