Hi anand, 

Its good to know you are serious about NEET exam. Since you are in 11th grade, try and concentrate more on basics. PCB is the core subjects in NEET. As long as your basics is strong , you can solve and crack any exams.

NEET Has more importance on few areas, most of which include 12th standard syllabus but 11th has the basics for 12th. Importanat focus are on:

Physics- Mechanics, optics,thermodynamics and nuclear physics.

Chemistry : mole concept, general organic chemistry,periodic table, chemical bonding and coordination chemistry. 

biology : ecology and environment, Genetics, cell biology, morphology , reproductive biology and basic biotechnology. 

All these , most are of 12th basics. So you need basics for these , which is foundation that happens in11th. You can follow these :

1) you need to know your syllabus

2) good books or study material - first prefer to study NCERT and then move to problems in physics and chemistry along with guides for biology.

3) have a scheduled study plan - you need to have  a deadline to learn basics and a thorough study plan according to you convinence to study basics and advanced.

4)focus more on weaker section - one which i you find difficult to understand at one go as it requires lots of effort if you dont understand and able to solve problems. 

5) solve more sample papers and take proper breaks in between - because our mind needs proper rest to process what you have learnt. 

6) maintain health and have proper sleep. Do not sacrifice health because when you stay healthy your brain works more and is more energetic.

7) BE pakka with NCERT . 

hope it helps, 

Good Luck.

Since you are 11th standard I would suggest you read 11th standard NCERT textbooks of Physics, Chemistry and Biology after which you can go for 12th standard NCERT Textbooks of Physics, Chemistry and Biology. 

After you finish one chapter from any of the subjects make sure to solve Multiple Choice Questions based on that chapter. This is because it builds your concept more stronger. 

The more questions you would solve the concept would become even more stronger. 

There are many reference books available for NEET Entrance Exam. You can choose whichever you want to but make sure you read that book well. 

Give equal attention to every subject as they all are equally important.

If you still have any queries feel free to ask in the comment section down below.