Well, my dear child, the people of Korea have stories they tell about how the world was created. They are called "creation narratives". Would you like to hear one?
According to one Korean story, there was a god named Hwanung who wanted to help humans who were struggling to survive. He came down to Earth and found a beautiful spot on top of a mountain where no one lived.
Hwanung built a city there and called it Sinsi, which means "City of God". He taught humans how to farm, hunt, and fish. But there was still something missing, Hwanung realized. He thought that humans needed to understand the importance of spiritual life as well.
So, Hwanung decided to give a special gift to one man and one woman in Sinsi. He left a tree with a ripe fruit hanging from it and gave these people the order to eat only ten cloves of garlic and then pray for 100 days in order to be worthy enough to partake of the fruit. The woman was named Ungnyeo and the man was named Hwanung.
Ungnyeo determined to eat the fruit herself and stand outside of the tree. Her attempts to jump up and reach the fruit caused her to transform into bear form. Hwanung himself completed his period of purification and ate the fruit from the tree, acquiring the power to become a human who could transcend the discord between Heaven and Earth.
Eventually, Hwanung passed away from this world and his son, Dangun, became the new ruler of Sinsi. Dangun is considered by some to be the mythical founder of Korea who introduced the agriculture, and settled the three kindreds Sibo(west)-Sibu(east)-Hamo(north).
So, this is how the Korean people believe the human world was created with the help of their god, Hwanung, and the story of his son, Dangun.