Since you belong to commerce background, you are eligible to apply for the flying branch as well as ground duty branch through the Air Force Common Aptitude Test also known as AFCAT. However, to apply for the flying branch, you must have studied Maths and Physics at +2 level. Apart from this, you must score a minimum of 60% in the bachelors degree examination.
The minimum eligible age to apply is 19 years and the maximum age limit is 23 years.