Herbivorous dinosaurs ate ferns, trees without fruits and seeds, and ate a lot of food every day to maintain their huge bodies. There seems to be no scientific research to show how fast dinosaurs ate, otherwise eating all day may not be enough to replenish energy.
Carnivorous dinosaurs, there are many delicious dishes on the table, including herbivorous dinosaurs, carnivorous dinosaurs, the possibility of swallowing each other, fish, arthropods, mammals and so on. You may also eat rotting corpses, etc.