Following is one of the way.
You need to qualify 11th and 12th with Physics, Chemistry and Mathematics with a minimum percentage of 55.
Then you have to apply for a DGCA class 2 medical certificate.
After that you need a class 1 medical certificate.
You need to visit the websites of different flying schools in India and apply for their entrance tests. You will face a written round, an interview and the notorious pilot aptitude test.
You must be prepared for science and maths related question from class 9 to 12, NCERT syllabus.
You will undergo an 18 month long training course. They will begin with theory, where you will learn the 14 subjects necessary to fly commercially.
The flight school will give you the necessary 200 flight hours. To gain those, you will fly with and instructor and finally all alone in a solo flight! In the end you will get a Commercial Pilot License.