Born on September 25, 2003, in Pančevo, Serbia. He graduated as the top student of his generation in 2022 from the "Dimitrije Parlić" Ballet School in Pančevo. During his education, he won second prize at the Republic Competition of Ballet Schools in Serbia. 

Upon graduation in 2022, Ćosić joined the ballet ensemble of the National Theatre in Belgrade, marking the beginning of his professional career. Over time, he has performed in a wide range of roles from the classical and contemporary repertoire while simultaneously engaging in choreographic exploration.

At the 28th Festival of Choreographic Miniatures in 2024, he received multiple awards for his first choreographic piece, "Creature Feature". These included the Encouragement Award, the Alexander Izrailovski Plaque for inventiveness and artistic expression, and the Audience Award.

In 2019, Ćosić was selected as one of ten participants in a prestigious masterclass led by the world-renowned Serbian performance artist, Marina Abramović.

ROLES IN BALLET PERFORMANCES:
• "Giselle" (L. Lavrovsky)
• "Don Quixote" (V. Vasiliev)
• "The Nutcracker" (K. Kostyukov)
• "Le Corsaire" (B. Yuldashev)
• "Infinitas" ("Symphonic Triptych," "Poem") (M. Kolar and I. Kirov)
• ”Ko to tame peva" ("Who’s That Singing Over There") (S. Zurovac)
• "Swan Lake" (K. Kostyukov)
• "Coppélia" (Lj. and P. Dobrijević)
• "Banović" Strahinja (I. Kirov)
• "Reflex" (S. Ninković)

ROLES IN OPERA PERFORMANCES:
• "Aida"
• "Carmen"
• "Die Fledermaus"
• "La Traviata"

FILM:
• The White Crow by Ralph Fiennes

AWARDS:
• "Encouragement" Award
• "Aleksandar Izrailovski" Plaque for innovation and artistic expression
• "Audience Award"