Hiii, 

All chapters are important but Thermodynamics ,Equilibrium,Electrochemistry are from physical carrying max marks.GOC is also very imp from organic. 

And periodic table from inorganic All chapters related to periodic are important..

Hope this will help you. 

Thank you. 

Assuming asking for JEE Main, Chemistry is divided in 3 parts:

Inorganic Chemistry

Organic Chemistry

Physical Chemistry

The topics Chemical bonding and S-block in inorganic chemistry, Alkyl Hallide, Alcohol & Ether (Reaction Mechanism) in organic chemistry and Mole Concept & Thermodynamics and Thermochemistry in physical chemistry were the high weightage topics.You can check 2018 Paper analysis with the given below link.
https://engineering.careers360.com/articles/jee-main-analysis

Good luck!