What character did Viola audition for in Will's play in shakesperas play?

In Shakespeare's play "Twelfth Night," Viola, disguised as the young man Cesario, auditions for the role of Viola in Duke Orsino's play. Although she doesn't actually perform in the play within the play, her role as Cesario allows her to interact with Orsino and Olivia, leading to the central conflicts and romantic entanglements of the story. The character she would play represents her own identity, which is central to the themes of love and disguise in the play.