Everyone's body is different in digesting food but it takes between 6 to 8 hours for peoples bodies to digest food fully and to poop it out.
Sometimes you may not even poop on the same day after eating but your food is still being digested.
I sometimes can eat food and then not poop until the next day unless I eat more fiber because the more fiber I eat the more often I poop.
The less fiber based foods I eat the less often I poop so you may not always poop after eating food if the food you eat is not very high in fiber content.
Still for most people the food is fully digested within 8 hours but sometimes it may take a bit longer depending on how much food you eat.