How to annotate data on the model ?

I’am a beginner. Now I have constructed a model.And I want to annotate some data on it.But I don’t know what kind of method can be achieved.So can you tell me about this,if you know.I will feel grateful.

I’m unable to tell you something like that…I think anyone who knows something about programming should already known the answer.
I think OpenGL programming is not for you…not yet IMHO.

“Annotate things” is the ABC of programming in any language…

And I want to annotate some data

Can you explain what you want a bit more. Do you want to draw labels in 3D or do you want to simple add comments to the data? If you want to add comments to the data, it depends on how you have the data stored. If it is in your program, you can comment it like any other part of your program. If it is in a file like .obj then you will have to edit the file but the format of the comment will depend on the file format itself.