were there any musical performances done by this fictional character?
Yes, many including the famous single  "Don't Stop Believin'.
Finn Hudson
As Finn is the most frequent male lead in New Directions numbers, Monteith features in a great many musical performances which have been released as singles available for digital download and are also featured in the show's soundtrack albums. He frequently shares vocal leads with the main female singer, Rachel, as in the pilot episode's closing song, Journey's "Don't Stop Believin', the single of which has sold over a million copies and been certified platinum in the US and Australia.
who wins prom king and queen on glee season 2 Kurt Hummel wins the Prom Queen. what is prom queen? An episode of a television series. what is this episode about? It shows the myriad dramas surrounding a high school prom, with the high-stakes race for prom king and queen that involves five members of the glee club, students scrambling to find dates and outfits, and the delights and disappointments of the prom itself. which channel airs this series? Fox . who composed the music for it? UNANSWERABLE who starred in it? Finn Hudson, Quinn Fabray, Noah "Puke" Puckerman and others. who is the first mentioned actor? He was a fictional character portrayed by Cory Monteith.
wiki:14361302
Finn Hudson [SEP] Musical performances
As Finn is the most frequent male lead in New Directions numbers, Monteith features in a great many musical performances which have been released as singles available for digital download and are also featured in the show's soundtrack albums. He frequently shares vocal leads with the main female singer, Rachel, as in the pilot episode's closing song, Journey's "Don't Stop Believin', the single of which has sold over a million copies and been certified platinum in the US and Australia. Like Finn, Monteith was a novice singer when the show started. In an interview with "GQ" Alex Pappademus, he noted that, early on, "you could hear the Auto-Tune." He was not called on to sing much on the first few episodes, as he rapped in "Push It" for "Showmance", had a short solo phrase in the song "I Wanna Sex You Up" in "Acafellas", and was not featured as a vocal lead in "Preggers".