Depends on what you mean. If you are hungry in general, you would say (나) 배고파. or 밥 (general food word or rice) 먹고 싶다. Or you can insert any food word instead of 밥 if you want to eat a specific thing.

Yes. Or (나는) 먹고 싶어 (반말) or (저는) 먹고 싶어요 (존댓말)