Starting his youth career with Sparta Sycewice, Czubak underwent a trial with Barcelona's youth teams in 2013.[2] Soon after, he joined Bałtyk Koszalin for one year before moving to Jantar Ustka. He started his senior career with the Pomeranian team, making his first IV liga appearance at the age of 15.[3]
In 2016, he was the top scorer of the Poland futsal under-16 championship, with Jantar finishing the competition as runners-up.[4] In the 2017–18 season of the Słupsk regional league, he scored 46 goals, aiding his team in earning promotion to IV liga Pomerania.[5] In June 2018, he joined Ekstraklasa club Śląsk Wrocław for their pre-season camp.[6] In the following campaign, he scored 23 goals in 33 matches.[7]
Bytovia Bytów
On 17 July 2019, he was transferred to third division club Bytovia Bytów.[7] He scored 18 goals and recorded four assists as Bytovia reached the promotion play-off semi-final, lost to Resovia Rzeszów after a penalty shootout.[8][9]
Widzew Łódź
On 13 August 2020, Czubak joined I liga side Widzew Łódź on a two-year deal.[10] He scored two goals in 17 appearances before leaving by mutual consent on 6 August 2021.[11]
Arka Gdynia
Hours after his Widzew exit, fellow second division outfit Arka Gdynia announced the signing of Czubak on a three-year contract.[8] He was the I liga top scorer in the 2022–23 season with 21 goals in 33 league fixtures,[12] including a hat-trick in a 3–0 away win over Sandecja Nowy Sącz on 26 February 2023.[13]
In September 2024, he extended his contract with Arka until mid-2026.[14] On 6 October 2024, he recorded his second hat-trick for the club in a 6–0 away win over Odra Opole, scoring all three goals in the first half. With this feat, he surpassed Grzegorz Niciński as the third best scorer in the Pomeranian club's history.[15]
On 24 November 2024, he entered the pitch in the 10th minute of Marcus Vinícius' farewell game, a home league fixture against Stal Stalowa Wola, replacing the Brazilian. Czubak went on to score his 63rd, 64th and 65th Arka goal during a 5–1 win, equalling and surpassing Vinícius as the club's best goalscorer of all time.[16]
International career
Czubak earned his first and only caps at youth international level in November 2019, making two appearances for the Poland under-20 team against Switzerland and Norway.[17]