Gilgamesh was not an ordinary person in fact he would be considered super human, gilgamesh was very mean to his people some people would pray to gods.
The goddes aruru made a beast man who was strong as gilgamesh. They named him enkidu a boy then spoted enkidu and tolled his father who tolled him to tell gilgamesh so the boy warned gilgamesh.
So gilgamesh gave the young man a beautiful women and named her shamhat he instantly fell in love with her he changed his heart so he was a kind man but gilgamesh still didn't get convinced he then battled enikidu.
finally gilgamesh won and enkidu accepted that gilgamesh is stronger they finally became freinds and as freind they loved adventure so one day they wanted to kill the demon in the forest so as enkidu was about to cut a tree roar the demon came out.
They called on the wind gods to trap him and then they finally had him the demon was beging for mercy but gilgamesh and enkidu did not care and killed it anyways the goddes of love then saw how strong gilgmesh was and fell in love
But gilgamesh regected her so she got mad and sent down the bull of heaven to distroy the city and him but they killed the bull the gods then got mad and as a punishment they killed enkidu but forgave gilgamesh becouse hes a god gilgamesh thougth that was so unfar and then relized he would die soon so he dicided to search for eternal life he found a couple that had enternal life he asked them how they said they deserved it so he dicided that seaching for enternal life is usless that he would instead leave a good city so thats what he did.