He first played basketball in an Atlanta church league when he was 4 years old. He became a high school star at Pace Academy in Atlanta, Georgia, where he was named the Georgia All-Classification Player of the Year and a first-team all-American.
He was the recipient of the 2017 Morgan Wootten National Player of the Year award, given to players who excel in academics and display exemplary character off the court.
His father, Wendell Carter Sr., played professional basketball in the Dominican Republic. His mother, Kylia Carter, played college basketball at the University of Mississippi.
He was teammates with Grayson Allen at Duke.