dark lighting?

Hey i am making a horror like game where i need a lot of dark areas so i got two questions about it 1 is when i need a dark room but if i dont have light its pitch dark and if i add a lamp or anyother light i its to bright any ideas on how to fix this and two not lighting related but and one know a good tutorial for a lod

Change the power of the light in the lamp tab. And then place lots of objects and stuff in the room. Move around different lights and tweak it the way you want it then bake the light on the texture.