Here is a write-up designed to accompany flute sheet music for the piece, along with a guide to playing it if you are looking to learn it by ear or transcribe it.
If you are looking for this specific scene's music, it is often grouped under broader theme titles: on the rooftop peter pan flute sheet music
While "On the Rooftop" is primarily an orchestral score piece, there are several ways to find arrangements or tutorials specifically for the flute: Here is a write-up designed to accompany flute