Hello Krishna,

I hope you are asking about improving in Mathematics. See, Many students find mathematics tough but it is not the toughest subject. You need to work on it to make it easy. 

Try to understand the concept first. After understanding any topic you will be able to solve the questions easily. Solve questions from the NCERT textbooks. It is the best book for basics. You should also refer to other important books for practice like RD Sharma. 

Mathematics is all about practice. Practice as much questions as you can to excel in the subject. 

Good Luck!