The CBD oil that you can get in any state is made from hemp, because it's illegal to make it from cannabis. If you're in a legal state, like mine, you can get hemp-based CBD oil from a regular store, or go to a dispensary and get cannabis-derived stuff. Usually the cannabis-derived stuff is whole-spectrum, with all the cannabinoids and terpenes and such, whereas the hemp-based may be isolated CBD and nothing else.

The other cannabinoids and terpenes often offer additional benefits. Both have them, but cannabis has more. Different strains of cannabis have different ratios of all this stuff; some strains have tons of THC and little-to-no CBD, and vice versa. When I get cannabis CBD, I just get a cannabis extract of a strain with very little THC, make it into an oil, and take a dose that doesn't have any psychoactive effect.