I bought a house that had the ground wire from the breaker box taken. A friend told me that the breaker box no longer has to be grounded

First thing is, never listen to friends with respect to electrical issues.

Second, what ground was taken? From the panel to the ground rod? Water pipe? What?
Your friend was predictably wrong also. You DO need grounding electrodes and water bonds. What you need, and what size, depends on the service.

Can you give us some more detail about this?

Somebody stole it for the copper. Definite need to have a ground. Can you see a water pipe or ground rod nearby?

Water pipes are not the best means of grounding. You don't know what kind of pipe is in the ground beyond your wall. It may not be metallic. A 6" copper clad grounding rod is the best choice. I speak from experience. I'm pretty sure that a lot of codes require grounding rods.

Rabeltz, your vast experience should be used to provide concise, accurate information.

Metal water pipe is the best grounding electrode, and if at least 10 feet of metal pipe is in contact with earth, it shall be the primary grounding electrode, and be supplemented with another grounding electrode.

The minimum size rod type grounding electrode shall be eight feet long x 5/8 inch diameter, not 6".