[4][3] Offiah made his professional footballing debut on 24 August 2021, coming on as a 68th minute substitute for Taylor Richards in the 2–0 EFL Cup second round victory over Championship side Cardiff City.
[5] He made his first start for the "Seagulls" on 8 January 2022, playing 55 minutes of the 2–1 – after extra-time – away win over West Bromwich Albion of the Championship in the FA Cup third round.
[7] Offiah was among the substitutes in Brighton's FA Cup semi-final against Manchester United at Wembley on 23 April 2023, where he remained on the bench in the eventual penalty shootout defeat.
[10] He made a goalscoring debut two days after signing, with a powerful header crashing in off the underside of the crossbar, scoring Hearts' second in the eventual 4–0 home win over Scottish Championship side Partick Thistle in the Scottish League Cup second round.
[12] On 30 August 2024, it was announced that Offiah would join EFL League One club Blackpool on a season-long loan.