Visit Zelda
Now, you can get out of Kokiri Forest and Saria gives you her ocarina. Go to Hyrule Castle but talk to Malon first, she is standing in Hyrule market, talk to her. Then go to Hyrule Castle. Malon is now next to the vines. Talk to her and she'll say something about getting her father. she'll give you an egg. Climb the vines and jump over the gate. Stay clear of the guards or you will have to start all over. By the castle moat, there is 2 guards, don't try sneaking past them. There is a portion of a wall that you can climb so climb it and jump into the moat. Climb up the opposite end nearby the tree. Then go to where Malon's father is. Your egg should be hatched by now so take it out and show it to him. he'll wake up and talk to him, then he runs really fast to get Malon. Rearrange the boxes of milk so that they are in a stack. Jump off the top and near the tunnel. Crawl through it. You have to do this during the day. Get pass through all the guards and you'll eventually end up seeing Zelda. Talk to her and she'll give you a letter. If you want more fun, shoot and break the window to Zelda's right and a man will come out and throw a bomb at you. if you peek through the other window using C-up, you'll see Mario, Bowser and some other people. Talk to Impa and she'll teach you Zelda's Lullaby.