Tre'Shaun Albert Mann was born in February of 2001 in Gainesville, Florida. He is the son of Albert Mann and Tai Bey and has five siblings. For prep school, Mann attended The Villages Charter School in Florida. During his junior season at The Villages, Mann delivered 20 points and 5.6 points per game. But he suffered a knee injury in the Class 5A-District championship game. Mann returned healthy for his senior season and boosted his scoring to 23.6 points per contest. That production led to Mann earning the Daily Commercial All-Area Player of the Year award. In August of 2018, Mann committed to attend the University of Florida. During the 2019-20 season, Mann started four of 29 games for the Gators and played 17.8 minutes per game. But as a sophomore, Mann started all 24 games for Florida and posted 16.0 points, 5.6 boards and 3.5 assists per game. Those stats led to Mann being named First Team All-SEC by the league's coaches. In March of 2021, Mann declared himself eligible for the 2021 NBA Draft. Mann was then selected by the Oklahoma City Thunder with the 18th overall pick.