Hello suhail

For understanding numericals you need to first clear all the basic concepts of how and on which questions you need to apply different concepts.

Use reference books for your numerical preparations

Reference books have lot of solved and unsolved numericals of all types from easy to hard levels.

If you can,please join a good institution,by joining you will learn new techniques for solving numericals.

Numerical part needs a better knowledge of concepts and formulas, it takes time,start doing your preparation from today

You will see results after sometimes.

Also try mock tests of JEE,they will help you in keep going.

Best of luck

And yes never give up

Hello,

Its better to set an aim to clear the exams.It will encourage you and will not let you give up.

Prefer some Best books such as H.C.Verma's for Physics , R.D Sharma's for maths and R.G Mukherjee's for chemistry.

Practice numorous problems and work hard.You will surely come up with flying colors.

Hey suhail, 

You should not give up buddy. You should keep in mind that "there's a will there's a way".

If you are determined you can clear it.  You can concentrate on your chemistry part. It can help you greatly.  Also focus on the conceptual questions more.  You can also start with basic numericals for chemistry and physics and gradually go To high level questions.  I suggest you too check out the HOTS part in your +2 text books all PCM,  they will help you ALot.  

Wish you all the best for future.