Siddhartha Gautama parents bring a astrologer to read the stars
your son  will either be a powerful ruler or a holy man and that the family will lose all power in the kingdom
His parents then protected him from all experiences. Siddhartha Gautama then grows up and gets married and has kids without meeting ordinary people outside of the palace.
Then one day he decides to leave the palace. When he leaves he sees an old man, a sick man, a monk, and a dead man.
Buddha wanted to find a solution to end peoples suffering so he left the palace and didn't return until he found a solution. He came to the conclusion after 49 days that humans are never satisfied and always want more.
Once Siddhartha became enlightened he became Buddha. He got some of his friends to be his disciples. Buddha wanted to break away from the Hindu way so he preached Nirvana. Once Buddha died he had lots of disciples to pass on his teachings.