Is it possible to earn money by knowing only python ? or should i learn anything else ?

Answer 1

Yes, of course!

Get a Developer Job.
Create a StartUp.
Freelancing.
Teach Coding Online.
Create a YouTube channel and Monetize it.
Create a Blog and Monetize it.
Join Coding Contests.

more info:
https://thepythonguru.com/how-to-make-money-if-you-have-JUMP_LINK__&&__python__&&__JUMP_LINK-skills/

Answer 2

At least you need to know frameworks in addition. And... Yes - with help of youtube it is possible to make mobile apps and earn money on ads