[6] Progressing through the City youth teams, he became a key player for the under-23 squad during the 2021–22 season, winning the Premier League 2,[7] whilst still playing with the under-18, as they also won the national competition.
[13] On 12 August 2023, Charles made his first appearance in the league for Southampton in a 4–4 draw against Norwich City, replacing Stuart Armstrong in the 65th minute.
[14] During a 0–1 victory against Queens Park Rangers on 23 December 2023, he received a red card following a second bookable offence for a foul on Albert Adomah.
[20] On 15 January, Sheffield Wednesday chairman Dejphon Chansiri confirmed during a fans forum, that Charles was being recalled by Southampton but would still be available for their next two games.
First called to the senior team by Ian Baraclough in May 2022,[5][8] Charles made his international debut for Northern Ireland on 2 June 2022, coming on as a substitute for George Saville in the 79th minute of the UEFA Nations League match against Greece.