Yes you can die from getting shot in the stomach and the death is usually caused by an infection called sepsis which slowly kills you over a few days and is a very bad and painful way to die.
So if you do get shot in the stomach you need prompt medical attention and need to either call 911 or get to the emergency room right away.
Getting shot in the chest or head is worse and can kill you sooner but getting shot in the stomach is deadly as well and is very painful.