[4] He converted to the point guard position at West Virginia, making his name as one of the top defensive players in the Big 12 Conference.

[12] On November 30, 2017, Carter became WVU's all-time leader in steals, surpassing Greg Jones' mark of 252 in a win over NJIT.

[13] On March 3, 2018, against Iowa State, he became the first major conference player to reach 1500 points, 500 rebounds, 500 assists and 300 steals in a career.

This award (Celebrating Loyalty and Achievement for Staying in School), given annually, is for the most outstanding senior student athlete in Men's Basketball.

Carter is the second player in West Virginia University history to win this award, the first being Da'Sean Butler, who won it in 2010.

[25] Carter made his NBA debut on December 15, 2018, coming off the bench in a 97–105 loss to the Houston Rockets with eleven points, two steals, a rebound and a block.

[26] On April 10, 2019, Carter scored a then-career-high 32 points along with four rebounds, two assists and a steal in a 132–117 win over the Golden State Warriors.

[28] On August 8 in the 2020 NBA Bubble, Carter scored a season-high 20 points on 7–10 shooting, including 6–9 from the three-point line in a 119–112 win over the Miami Heat.

On August 6, 2021, Carter and the draft rights to Day'Ron Sharpe were traded to the Brooklyn Nets in exchange for Landry Shamet.