About me: Superboy-Prime was raised on a parallel world dubbed Earth-Prime. He was thought to be a normal child. He was adopted by Jerry and Naomi Kent, who named him Clark, Naomi's maiden name, and after the fictional comic book character in their world. It turned out he really was Kal-El and was teleported to Earth-Prime before the Krypton of this universe was destroyed when its sun Rao went supernova.
The Superboy of Earth-Prime left his reality shortly after discovering his new abilities as Halley's Comet passed by activating his Kryptonian powers, while coincidentally dressed as Superman at a Halloween party. In a twist of fate the Earth-One Superman was passing by and saw yet another Superman and asked him to join other heroes in protecting reality itself from the Anti-Monitor during the Crisis on Infinite Earths. His reward, along with Alexander Luthor, Jr. of Earth-Three, Golden Age Superman, Kal-L, and Lois Lane of Earth-Two, was a chance to escape to an apparent heavenly pocket dimension before reality fixed itself after the Crisis.