Miller attended Christian Brothers High School in Memphis, Tennessee, where he played football and ran track for the Purple Wave athletic teams.

[9] In his NFL debut against the Green Bay Packers in the season opener, he had two receptions for 14 yards in the 24–23 defeat.

[12] On October 14, caught a 29-yard touchdown pass against the Miami Dolphins, his second of the season, in the 31–28 overtime loss.

[15] In Week 13 against the New York Giants, Miller caught the game-tying touchdown pass in regulation on a trick play: quarterback Chase Daniel tossed the ball to tight end Trey Burton, who then tossed it to running back Tarik Cohen, who threw it to Miller for the touchdown.

In addition, fellow Bears wide receiver Josh Bellamy and 49ers cornerback Richard Sherman were ejected from the game.

[20] Against the Lions in Week 13, Miller finished with a career-high nine catches for 140 receiving yards as the Bears won 24–20.

[21] In the following week's game against the Dallas Cowboys, Miller caught three passes for 42 yards and his first touchdown of the season in the 31–24 win.

[24] In the 2020 season opener against the Lions, Miller scored the go-ahead touchdown with 1:55 remaining on a 27-yard reception from Trubisky; Miller's assignment, a fly route from the right slot receiver position, was the same pattern he ran in the 2019 Thanksgiving game that resulted in a 32-yard catch.

[25] In Week 3 against the Atlanta Falcons, Miller caught a 28-yard touchdown pass late in the fourth quarter to help the Bears come back to win the game 30–26.

[27] Miller was ejected from the Wild Card Round of the 2020–21 NFL playoffs for hitting New Orleans Saints cornerback C. J. Gardner-Johnson.

[47] Miller was elevated to the active roster for the Ravens' playoff game against the Buffalo Bills, a 27–25 loss.