He played college football for the Washington Huskies, Central Michigan Chippewas and Northern Colorado Bears.
[3][4] Sirmon attended Bothell High School and was a top quarterback, throwing for a career 5,786 yards and 47 touchdown passes while being first-team All-KingCo and the 4A KingCo offensive most valuable player as a senior, as well as an invitee to the Under Armour All-America Game.
[8] He competed for the starting job in 2020 but lost to Dylan Morris, finishing the season with one game played while completing his only pass for nine yards.
[6] In his first season at Northern Colorado, Sirmon appeared in seven games and completed 52-of-93 passes for 595 yards and four touchdowns, with two interceptions.
[12] After going unselected in the 2024 NFL draft, Sirmon was signed by the Cleveland Browns as an undrafted free agent following his performance at the team's rookie minicamp.