Vertebrates including ourselves have a digestive system.
The digestive system begins with a mouth to ingest food and often chew it. Once food is swallowed it goes into the stomach where a series of enzymes break the food down. The nutrients are kept in the body and the bulk of indigestible material passes into the intestines first the small and then the large.
It is important to note that the length and properties of the digestive system differ from to species. This often depends on the diet of the species. Carnivores such lions have a relatively short digestive system and a stomach lacking the enzymes we have. Herbivores typically have much longer digestive systems than ours in order to process the large bulk of fibrous foods they consume. Our system is of an intermediate length and we excrete enzymes to break down out food in the stomach.
At the end of the large intestine is the rectum and vertebrates will pass feces excreting the wastes from their bodies.
Urine is the liquid waste we also excrete which collects in the bladder and comes out of the urethra.