Brylian Aldama launched his footballing career in his hometown of Surabaya through the youth system of Persebaya. After playing for several Indonesian national junior teams in different age groups from 2018 to 2020,[2] he attracted top-flight Croatian club HNK Rijeka that recruited him to play for their youth team in the first half of 2021. After a few non-league matches, he failed to earn a spot on the roster, leading to a loan spell at NK Pomorac 1921, which plays in the third-tier of Croatian football. He played several matches for Pomorac's junior team and even scored goals for them but injuries blocked his progression.