So i would like to try a culture some of my keratinocytes just to see if i can do it. Ive read about a few different types of growth medium such as DMEM and RPMI but i am not sure about when to use which medium. So I am asking how do i detrimine which growth medium i need to use to culture human cells
So this paper probably has what you need. Isolation and cultivation of human keratinocytes from skin or plucked hair for the generation of induced pluripotent stem cells
The first part of that paper covers just the cultivation of keratinocytes. It's actually moderately difficult to culture keratinocytes, so if you just want to try out cell culture I wouldn't recommend this as your first step.
A good first step to learning the techniques of cell culture would either be bacterial, fungal, or yeast cultures because they are cheap, hardy, and don't require expensive equipment. Yeast culturing would be closest in technique to mammalian cell culture among the three Yeast culture info here