Arnold was born in
Atlanta, Georgia and grew up in
Denton, Texas, where he attended
John H. Guyer High School.[2] As a freshman and sophomore he was mainly the backup to future Texas A&M quarterback Eli Stowers.[3] As a junior, Arnold passed for 3,921 yards 34 touchdowns and also rushed for 659 yards and 12 touchdowns.[4] He was initially rated a four-star recruit and committed to play college football at Oklahoma from 25 scholarship offers.[5][6][7]
Arnold participated in the finals of the 2022
Elite 11 quarterback competition and was named the tournament's MVP.[8][9] Entering his senior year, he was re-rated a five-star recruit.[10][11][12] At the conclusion of his senior year at Guyer, Arnold was named the 2022 winner of the
Landry Award, given annually to the top high school football player in the
Dallas-Fort Worth Metroplex.[13][14] Arnold was named the
Gatorade National Player of the Year following his senior season.[15]
College career
Arnold joined the
Oklahoma Sooners as an early enrollee in January 2023.[16] He entered his freshman season as the backup to starter
Dillon Gabriel.[17] Arnold made his college debut in the Sooners' season opener against
Arkansas State, entering the game in the third quarter and completing all 11 of his pass attempts for 114 yards and one touchdown and also rushing for 39 yards and one touchdown in a 73–0 win.[18]
Following Dillon Gabriel's transfer to Oregon in December 2023, Arnold was named the starting quarterback for Oklahoma's bowl game against Arizona.[19]