Canosa first attended Atlantic Union College, then transferred to Harvard College (class '93). There he directed several plays and videos. While at Harvard, Canosa also met his partner Gabrielle Zevin when she was a cast member in a campus TV show he worked on. Zevin would later go on to write the screenplay for Conversations with Other Women, and for Canosa's 2022 film The Storied Life of A. J. Fikry, adapting her own 2014 international bestseller.

He later entered New York University's graduate film program, but dropped out when he felt it was too restrictive for him.