Put the boots on when you enter here. Then at the back of the island is a rock. Smash it with your Skull Hammer. The wind will go away and you will be able to proceed on. On the back wall is the song in which you must learn. Play it and learn the Wind God's Aria. Then the Kokiri Sage comes out and tells you to find a violin player. Well, remember the Makar from the Deku Tree. He celebrated the ceremony with the violin. We must find him as we found Medli. Go back and warp to the Forest Haven.