I've can keep popsicles, jello, and clear liquids down. how can i rehydrate myself, and how can i naturally work my way up to hard to digest foods?

Start slow, increase: Start with sips of fluids (no caffeine; flat 7 up ok) to prevent irritated stomach from stretching (=vomit). Gradually increase amt. For solid foods, try brat diet: banana, rice (cooked, no milk), applesauce, toast (plain, unbuttered). Pepto-bismol may also help settle stomach. If no improvement, see fp for evaluation & treatment.