After 12th, to become a commercial pilot, you should have Commercial Pilot Licence. This Licence is issued after a candidate clears the training program from an Institute recognized by the Civil Aviation Authority of that particular country (DGCA in India).

To be eligible for a commercial pilot license, the applicant must be able to read, speak, write, and understand English: already hold a private pilot license, have received training in the areas of a commercial pilot, and successfully complete the relevant written exams.

In 12th, you should have PCM with 50%. A Commercial Pilot has to be fit- physically and mentally. That’s why, during the selection process, lots of emphasis is laid on the medical status of the candidate. Eye sight and Phyical deformity is checked.

There is an Pilot Aptitude test and after you clear this exam you will be required to give interview and then aptitude test. Then clearing the above 2, you will be required to clear medical examination. You will require flying experience as well, and as a fresher, the training will be of  15-18 months.

This is the main process to become a commercial pilot. There are other 2 pilot liscence, namely, student license and private license..

Good Luck.