2d map with OpenGL based on openstreetmap data

Hi all,

I’m totally new to OpenGL so I hope to get some help here for my first “project”
I need a kind of a kickstart to get me started.
What I want is draw a 2d map based on parts of openstreetmap data .
But I don’t have a good Idea how to start.
How to align the OpenGL corrdinate system with the lat /long values from OSM?
If anyone could give me some general hint, I think that would help me a lot. Ahhh btw: it will run on OpenGL es. Just for completion.
Thanks in advance !