Complex sentence: Gaines was born in Chicago, Illinois, but traveled over the U.S. as a child and eventually landed in Oakland, CA, where he attended Castlemont High School, adjacent to Youth UpRising.
Split into simpler sentences: Gaines was born in Chicago, Illinois, but traveled all over the U.S. as a child. He eventually landed in Oakland, CA, where he attended Castlemont High School, which was adjacent to Youth UpRising.