A central midfielder,[4] Yarmolyuk is a product of a number of youth sportive schools of the Dnipropetrovsk Oblast and in May 2019, at age 15, he signed a three-year contract with Ukrainian Premier League club SC Dnipro-1.
[2] Yarmolyuk's second appearance made him the second youngest player to start a match in the history of the Ukrainian top flight, at the age of 16 years and 140 days.
[2] On 14 July 2022, Yarmolyuk transferred to Premier League club Brentford and signed a three-year contract, with the option of a further year,[9] for a fee reported to be €1.6 million.
[17] He returned fit for the 2023–24 pre-season and made his first appearance of the regular season with a start in a EFL Cup second round shoot-out win over Newport County on 29 August 2023.
[24] Yarmolyuk made four appearances in the tournament, scoring once and he converted a penalty in the shoot-out that decided the final versus Ivory Coast in Ukraine's favour.