Complex sentence: He attended New York City's High School of Music & Art and was classmates with Laura Nyro and Michael Kamen and in 1963, as a sixteen-year-old, Randall met Richie Havens in Greenwich Village and began gigging.
Split into simpler sentences: He attended New York City's High School of Music & Art, where he was classmates with Laura Nyro and Michael Kamen. In 1963, at sixteen, Randall met Richie Havens in Greenwich Village and began gigging.