Can anyone tell me that from which chapter chemistry if hadn't studied anything in chemistry class 12.

I haven't studied anything in chemistry.
I want to know that from which chapter to start with..... For scoring good marks.

I haven't studied anything in chemistry.
I want to know that from which chapter to start with..... For scoring good marks.

See if you haven't started anything then, i think you should go for Organic Chemistry first. If you can remember the name reactions thoroughly it will be a great bonus to you. Then , i think you should go for Physical Chemistry. It mostly contains some stupid and easy definition and derivation and some questions which are mostly formula based. Just try to by heart the formulae of Physical Chemistry.  Then , if you have some time go for Inorganic Chemistry. Personally i feel that it is the toughest. It is very hard to remember.  If you still have some doubt , ask me. I hope you score really well. All the best.

Thanks for telling me.

Its okay.

Can you also help me in physics.

Yeah, first start with modern physics. Often people forget modern physics as it is in the end and they just don't think it is very good scoring topic. So first just be thorough with Modern physics and Optics . Once you are done with that, then go for Electricity and Magnetism. See , Communication systems , Electronic device, EM Waves, Dual Nature, Atoms and Nuclei are not that complicated chapters . So just read NCERT and it will be more than enough to tackle board questions. After that i personally considered to go for Electrostatics and Current Electricity.  Once you are done with that go for Optics the portions of Optics are not very much and contains large marks for it. So don't miss out on that. I considered Magnetism to be a bit more difficult. So i think you should go for that at the last to be a bit more confident in that area. All the best for your exams and i hope you score really very well.