With the right guidance and with good practice 60+ score is easily achievable.
If you are targeting 60+ marks in JEE Mathematics, attempt at least 20 questions (Assuming 80% + accuracy)
First of all, you have to revise the class notes (If you have taken coaching from a standard institute) and solve all the questions discussed in the class and remember all the formula by heart (Specially Trigonometry and integration formula)
Then you should practice at least 50 different types of questions from every chapter, and look for alternative methods or shortcuts to save time in the exam.
Write at least 1-chapter wise mock test and 5–10 full syllabus mock tests before your final exam.
Here is the list of Important chapters with the expected no of questions that can be asked in JEE Mains 2021 (Feb shift)
1. Vector and 3D (2-3 Questions)
2. Limits continuity and differentiability (2-3 Questions)
3. Conic section (2-3 Questions)
4. Application of derivatives (2 Questions)
5. Matrix and Determinants (2 Questions)
6. Definite Integration and Area under the curve (2 Questions)
7. Set Relations and Functions (1-2 Questions)
8. Sequence and series (1-2 Questions)
9. Point and Straight line (1-2 Questions)
10. Quadratic Equation) (1 Question)
11. Probability (1 Question)
12. Complex Number (1 Question)
13. Mathematical Reasoning (1 Question)
14. Statistics (1 Questions)
To get 60+ marks in JEE Mains at least these topics you have to do. Some extra topic you can do to be on the safer side
1. Differential Equations (1 Question)
2. Binomial Theorem (1 Question)
3. Permutation and Combination (0-1 Questions)
4. Inverse Trigonometric Functions (1 Question)