I have problem choosing between 2 life purpose.

[LordFall]

I would absolutely do stuff related to biology; biotech in particular is gonna be a booming field throughout the next 20 years. There's no reason you can't do art on top of it though; just flesh out what that looks like. The career paths of a biologist and an artist are very different but you can be a biologist that posts art on his social media and either integrates it or not. 

A better question is what have you done so far and how far in your career path are you?