"Khan" is a name that some people have. It usually comes from parts of the world where people speak languages like Arabic, Persian, and Urdu. Sometimes it can also be a title that people use to show respect for someone in charge, kind of like calling someone "Mister" or "Mrs."
So, if you meet someone named Khan, it's just a name they were given, like how your name might be Jason or Emily. And sometimes, Khan might be used like a special nickname to show someone is important and respected.