Lewis starred at
Bishop O'Connell High School in
Arlington, Virginia and chose
James Madison University (JMU) for college. He entered the starting lineup for the Dukes, averaging 14.5 points and 3.5 rebounds per game in his freshman season, earning
Colonial Athletic Association (CAA) All-Rookie Team honors. Lewis followed this up with a sophomore year where he averaged 16.4 points, 4.2 rebounds and 3.2 assists, garnering third-team All-CAA honors. In his junior year, Lewis again improved his scoring average to 19 points per game and earned second-team All-CAA honors, though the Dukes experienced little on-court success, finishing in last place. After head coach
Louis Rowe was fired, Lewis chose to declare for the
2020 NBA draft, though he retained his college eligibility by not hiring an agent. Ultimately Lewis decided to return to JMU for his senior season under new coach
Mark Byington, who helped advise Lewis and his family through the testing process. In advance of his senior season, Lewis was chosen as the preseason CAA Player of the Year, although the Dukes were predicted to finish ninth in the 10-team league. While the
Dukes' 2020–21 season were paused several times due to
COVID-19 protocols, both Lewis and the Dukes team experienced success. Lewis was named the national player of the week by the
United States Basketball Writers Association on January 17, 2021, after hitting a school record nine
three-pointers in a 30-point effort against
Towson. Lewis' 2020–21 season ended prematurely when he suffered a knee injury on February 14, 2021, and was later ruled out for the remainder of the year. On March 5, he was named the 2021
Colonial Athletic Association Player of the Year. ==Professional career==