In March 2018, Dosunmu was named one of 26 high school seniors who participated in the Jordan Brand Classic on April 8, 2018, at the Barclays Center in Brooklyn, New York.

[4] Dosunmu was also selected to play in the second annual Iverson Roundball Classic All-American Game in April 2018 at Souderton Area High School outside of Philadelphia, Pennsylvania.

[5] During his senior season, Dosunmu averaged 25.2 points, 7.4 rebounds, 7.3 assists and 2.7 steals, leading Morgan Park to a second-straight IHSA Class 3A championship.

On October 19, 2017, Dosunmu verbally committed to play college basketball for Illinois and head coach Brad Underwood.

Dosunmu announced his commitment to Illinois over Wake Forest at the flagship Jordan Brand Store on State Street in the Chicago Loop.

Sources: Dosunmu made his college debut on November 8, 2018, against Evansville, recording 18 points on 8-of-15 shooting, with six rebounds, four assists and three steals.

[24] On March 14, he recorded 16 points and nine rebounds in a 91–88 win over Ohio State in the Big Ten Men's Basketball Championship game.

[25] Dosunmu was a consensus first-team All-American and won the Bob Cousy Award as top point guard in the nation.

[31] On January 25, 2022, Dosunmu opened with nine consecutive made field goals, surpassing Orlando Woolridge's Bulls rookie record of eight.

[7] Dosunmu won a gold medal with the U18 National Team, while averaging 9.5 points, 4.5 assists and 2.3 rebounds during the international competition.