Okay. A cartridge is a complete unit of ammunition, so it consists, in general, of four components. You have a cartridge case, which is the overall container. You have the propellant powder, which is inside the cartridge case. You have a primer, generally at the rear of the cartridge case, which is what the firing pin strikes and what is used to initiate the discharge of the cartridge. Lastly, you have the bullet, which is at the front of the cartridge. It's seated in the mouth of the cartridge.
When a typical hunting rifle is fired, the propellant powder will be consumed. The bullet will be launched from the muzzle of the firearm and travel down-range to strike the game animal. The cartridge case and primer will remain inside the firearm and be ejected by the firearm operator.