First you need to do masters after MBBS. After that you have to serve as senior resident for at least 3 years. Then, after 3 years of residency you can serve as assistant professor. Then, based on your performance, you are promoted to post of associate professor and finally you are promoted for the post of professor.
The promotion from Assistant P to P will depend on the research papers written, performance reports by seniors, seniority, vacant posts, conferences attended, workplace politics, rules of the state etc.

Hi Dharani Bala

Different institution have different criteria for selection. Also the stream or subject of which you want to be a professor varies a lot. It also depend upon the vacancy and urgency and the qualification of other candidates who have applied.

please send some more details of you field of interest.

All d best

dear student

 A master degree will be the minimum requirement to be a professor, as a career, in most community and two-year colleges. However, you may need a doctoral degree to attain the rank of professor in the same institutions. You need a doctoral degree and post-doctoral experience for any comprehensive university.

hope it helps

All the best!!!