need some extra income as a doctor

i need to earn some extra income as a doctor. medical surveys not a good option for me because im a asian. survey opportunities very less for asinan countries

YouTube is one nice way to start making money online without any investment apart from time. As a Doctor, you may start a channel related to health & fitness, which is always an evergreen niche.
And the same (YouTube ) and many other similar methods can be found in the https://www.blackhatworld.com/forums/making-money.12/ section. In certain methods a bit of money needs to be invested such as for domain, website hosting, etc, which are not big amounts of investment. Wish you all the best.

Welcome. It will be more harder than your surveys. But, Its possible