Any advice for painting concrete?

Hi everyone.

I want to paint the concrete walls in my basement. They are poured concrete.

Do I need to prep the surface with a primer first or can I just start painting? Is there a concrete specific paint I should use or should I use a good exterior paint? I want to use gloss paint. I'll be using a roller and brush. Yes spraying would be ideal but not what I'm doing.

Thanks everyone.