Born on 14 May 2005 in Créteil, Housni played for various clubs in the Île-de-France region, including Bonneuil, Aubervilliers, Paris FC, and Joinville. He eventually joined Paris Saint-Germain at the age of 14. Alongside Ismaël Gharbi, Warren Zaïre-Emery, and El Chadaille Bitshiabu, Ilyes honed his skills in the youth academy and signed his first professional contract with Les Rouge et Bleu until 2026 on 30 December 2022.
As a member of the U19s, the Parisian forward established himself as an essential player and scored numerous goals leading Zoumana Camara's attack. Just coming of age, the Franco-Moroccan player became a French champion in the 2022/2023 season with the club from the capital, appearing in 2 matches and contributing to his team's eleventh title win. In the 2023-2024 season, the "titi" was loaned to Al-Sadd SC in Qatar.
