You start in a little house with a roommate. You go and discover a little "cabin" in that cabin you see a stairway, you go down that stairway and you are in a cave... After that you discover the cave a little and then you see a doorway, you go through it and you end up in a dungeon way in the dungeon you meet Kevin, he tells you that he needs you to defeat Moon Lord, you get some usefull things from him and after that you defeat Lunar Cultists, the Pillars and Moon Lord...
BTW if you only get the file "Phillip" then go to the selection "Files" and download the files there....