pictures dark in manual mode

what setting is making the pictures so dark in manual mode?

Most likely the shutter speed is to fast or the aperture isn't wide enough for the available light.

thanks I will look into that. there was a few settings I would change and the picture on the LCD would become brighter, but when I took the actual picture it was still dark

ok I got it. it was the shutter speed being too fast

If the pictures are too dark, you need to have your aperture at the widest (f/2.8 at 5 mm, f/5.7 at 100 mm) setting, increase the ISO, and decrease the shutter speed (use 1/30 or 1/15, say, rather than 1/60). Just be aware that slower shutter speeds will capture motion, both in your subject and in your hands, much more than will fast shutter speeds.

Bryan Peterson's "Understanding Exposure" is a good book that explains some of the basic concepts of photography.