Help me : I want to show a pyramid

Dear,
I want to show a pyramid. I’ve already use some light function. But wht I can see on screen isn’t in 3D effect. I think I must use some shading function. Please tell me how to solve my problem.
Thanks to answers.

What do you mean by: “But wht I can see on screen isn’t in 3D effect”
Did you calculate the normals for the faces?

I’ve tried to do it, the situation seems better. Now, I want to view a terrain model
and need some texture.
Please let me know your advice.
Thanks