Host for Flask App?

Question

Which is best Host to deploy my Flask app with MongoDB

Answer 1

If you are a beginner or project isn't serious, you can use pythonanywhere.com. Another free hosting is Heroku, but it's harder to deploy, because u need to install all packages on your own. If you have money, you can search any VPS hosting (virtual private server)

Answer 2

Okay, I've tried pythonanywhere.com
but it shows HTTP 500 (internal server error),
no bugs, all the modules are installed and imported correctly.... but what maybe the problem?