What would be the best time to become an Actor?

Well there is no best time to become an actor! you can pursue acting even in old age. But then it is more like passion and hobby than a stable career (which only comes to a very few). Wish you the best for your career. Remember, your Career is a resultant of your knowledge combined with your passion

There were some in Telugu who became actors after 60 and they became famous also. It all depends on the inherent talent. There is no prescribed Age. But, it is better to start early to achieve more and get more money.