Gates attended St. Francis High School. Alongside teammate Kobi Simmons and Malik Beasley, he led the team to two, back to back, state titles. Gates finished with more than 1,200 points and is the school's all-time leading rebounder. He was regarded as three-star recruit and the 10th best player in Georgia by 247 sports and selected Xavier over offers from Texas Tech, Vanderbilt, Florida State, Georgia and Missouri.
College career
Gates posted 3.2 points and 2.6 rebounds per game as a freshman. He missed the first five games of his sophomore season with a knee injury. As a sophomore, Gates averaged 5.8 points and 4.1 rebounds per game and played an important role in Xavier's run to the Elite Eight. In a win over Florida Statein the Round of 32, he contributed 14 points, five rebounds and two assists. Gates averaged 7.2 points and 4.6 rebounds per game as a junior. He was a strong defender and shooter, hitting 37.8 percent of his three-point attempts. Gates stated 22 games as a junior, with most coming in the first half of the season. After the season, Gates declared for the NBA draft and hired an agent, thus forgoing his senior season at Xavier. He finished his career with 533 points.
After going undrafted in the 2018 NBA Draft, Gates signed with the Chicago Bulls for NBA Summer League play. He averaged 6.7 points and 1.7 rebounds per game in three games. Gates signed a training camp contract with the Bulls on September 14, 2018. He was waived by the Bulls on October 12, 2018. Gates was added to the training camp roster of the Bulls' G League affiliate, the Windy City Bulls. On October 18, 2019, the Celtics waived Gates. Gates played in all 50 of Windy City’s games, averaging 12.7 points and 6.5 rebounds per game.
On September 12, 2019, his returning rights were traded to the Maine Red Claws for the #4 overall pick in the 2019 G League draft. On January 9, 2020, Gates finished with 24 points and 10 rebounds and made a buzzer-beating game-winning layup in a 120-118 triple overtime win over the Capital City Go-Go.