if any one want to clear both neet and jee main but he is a biology student then which chapters should he do for maths,

Below are the Important chapters for Maths

MATHS:-

Do OR DIE TOPICS

Probability -around 7%
Definite Integration -around 6%
Circles -around 5%
Vectors -around 5%
Theory of Equations -around 5%
Sequences and Series -around 5%
Complex Numbers -around 5%
3D -around 5%
Matrices and Determinants -around 4%
Differential Coefficient -around 4%
Sets Relations and Functions -around 4%

IMPORTANT TOPICS

Application of Derivatives -around 4%
Trigonometry -around 5%
Parabola -around 3%
Limits -around 3%
Heights and Distances -around 2%
P&C -around 2%
Straight Lines -around 2%
Areas -around 2%
Differential Equations -around 2%
Continuity and Different-ability -around 2%

LEAST IMP.

Other Conics
Binomial Theorem
Mathematical Induction
Prop of Triangles
Statistics
Pairs of St.Lines

For preparation NCERT book is good to clear you concepts but to score good marks you should go for other recommended books.

Below are some good recommended books for your preparation

1- Maths XI & XII by R.D. Sharma
2- Plane Trigonometry Part 1 by S.L. Loney
3- Plane Co-ordinate Geometry by S.L. Loney
4- Higher Algebra by Hall and Knight
5- Problems in Calculus of One Variable by I.A. Maron