I have not taken any extra coachings for preparing for jee n my 12 concepts r ok but 11 not good will only the revising of formulas be ok.

You can first focus on important chapters for your revision which carries more weightage in the exam. You can go through important notes if you have prepare than, revise all the formulas.
Solve previous year papers to understand the exam pattern and level of questions. Solve complete mock test series to analyze your preparation level and to know your strength and weakness.

You can check below important topics for your preparation-

PHYSICS :-

THE MOST IMPORTANT CHAPTER ( DO OR DIE ) CHAPTERS

Electrostatics - around 9%
Heat and Thermodynamics -around 8%
Rotational Motion -around 7%
Wave Motion -7%
Laws of Motion -around 6%
Simple Harmonic Motion -around 5%
Wave Optics-5%
Units Dimensions and Errors -around 4%
Work Power and Energy -around 4%

IMPORTANT TOPICS (Should do) CHAPTERS

Modern Physics -around 4%
Current Electricity -around 4%
Electromagnetic Induction -around 3%
Physics of Nucleus -around 3%
Fluids -around 2%
Gravitation -around 2%
Elasticity -around 2%
Solids and Semi conductor Devices -around 2%
Center of Mass , Momentum and impulse -around 2%
Kinetic gases -around 2%
Radioactivity -around 4%

IF YOU HAVE TIME GO THROUGH THESE TOPICS

AC,
EMW (Electro Magnetic Waves)
Vectors
2D
Circular motion
Capacitance
Kinematics

CHEMISTRY:-

DO OR DIE CHAPTERS

General Organic Chem -around 9%
Alcohol Phenols and Ethers -around 7%
Redox Reactions -around 6%
Chemical Bonding -around 5%
Coordination Chem -around 5%
Inorganic Chem -around 10%
Aldehyde and Ketones -around 5%
Solutions -around 5%
Solid State -around 5%

IMPORTANT TOPICS

Chemical Thermodynamics -around 5%
Ionic Equilibrium -around 3%
Chemical Equilibrium -around 3%
Surface Chemistry -around 3%
Periodic Classifications -around 2%
Atomic Structure -around 2%
Metallurgy -around 2%
Gaseous State -around 2%
D and F block -around 2%
Polymers -around 2%

OTHERS:-

Chemical kinetics
Biomolecules
Electro chem
other organic topics

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