[4] At the age of 16, he started working as a janitor at a hotel in Central prior to graduation and only scored one mark in the Hong Kong Certificate of Education Examination.

[4][5] He also entered into a relationship with a Chinese girlfriend and nearly got married, but ultimately ran away from the wedding and returned to Hong Kong.

[4] Upon his return to Hong Kong, he did not find any job until his newfound girlfriend encouraged him to pursue a career in modeling.

[9] In 2015, Cheung starred as Jack, the main villain and co-leading role, in the crime film Imprisoned: Survival Guide for Rich and Prodigal alongside Gregory Wong.

[11][12] Cheung achieved breakthrough success with his portrayal of Jiu Jik, a maniac gangster, in the crime thriller web series OCTB [zh].

[13] He immersed himself in the character through method acting, dying his hair and eyebrows white, and spending two months with real gangsters.

[22][23][24] In 2019, Cheung made his producer debut and starred as Chui Chit, the male protagonist, in the mystery film Deception of the Novelist [zh].

[29][30][31] Cheung established a toy brand called NiL and in 2022, he launched an NFT featuring a cartoon version of Jiu Jik.

[20] Cheung dedicated about a year to undergo method acting and reconnect with Jiu Jik's personality and mindset before the start of filming in 2023.