Osong joined Nottingham Forest as a youth in 2017 from grassroots football in Leicestershire,[2] and worked his way up their youth sides. He had a prolific start with the club's U18s in the 2022–23 season, scoring 12 goals in 20 appearances.[3] He signed his first professional contract with the club on 6 January 2022.[4]
On 1 February 2023, Osong made his professional and senior debut with Nottingham Forest in a 2–0 EFL Cup loss to Manchester United.[5]