Besides wine, what else was a Nazirite forbidden to eat or drink?

Answer: Anything from the grapevine

A Nazirite abstained from wine and strong drink and ate nothing from the grapevine, not even the seeds or skins.

“he is to abstain from wine and strong drink. He must not drink vinegar made from wine or strong drink, and he must not drink any grape juice or eat fresh grapes or raisins. All the days of his separation, he is not to eat anything that comes from the grapevine, not even the seeds or skins.”— Numbers 6:3-4 (BSB)