Dear Naveen,

There are many students who have crack JEE Main exam without coaching Institute. It all depends on your determination and hard work.

Coaching Institutes can only guide you but ultimately you have to work hard to acheive success.

To score good marks in JEE Main make sure you have strong base. You can take help of NCERT books to make your concepts strong. It will help you to solve tricky questions.
It is recommended to use right study material. Don't run after many books.

You can recommended below book after NCERT.
Physics
HC Verma
DC Pandey

Chemistry
Organic Chemistry- O.P Tandon
Modern Approach to Chemical Calculations- R.C. Mukherjee
Numerical Chemistry- P. Bahadur

Mathematics
R.D. Sharma

Focus on the topics which carry more weightage in the exam. It will help you to score good marks.

Refer previous year papers to understand the exam pattern and level of questions. So, that you can plan accordingly.
Practice plays a important role in scoring good marks. You should solve complete mock test series to analyze your preparation level and make sure you do proper analysis of your exam. So, that you can improve your performance. It is very important that you learn from your mistakes.

All the best for your preparation!!