After leaving the Sparring Hall, run ahead, back along the path. If you’re playing the Wii version, you’ll automatically stop and notice a Sheikah Stone (ahh… Ocarina of Time has influences even now). Just watch the scene; it is fairly self-explanatory. Meanwhile, nothing will happen in the Switch version…
After the scene (or otherwise), go along the path and back to the Bird Statue. Use it if you want to, then go through the gate and downstairs. At the bottom. go left and along the wooden boards to find the waterfall. Hop across the rocks (be careful about falling - you will fall, albeit unhurt) to the other side. There, go up the incline to the waterfall entrance. Cut down the blockade and walk inside.
Upon entering, go forward and look to the right; you’ll see a fence. Go to the opening in said fence and jump down the below ledge. You’ll find a chest on the other side of the gap with a Red Rupee inside.
Drop down and continue, defeating the Chuchus and the Keese as you go. You’ll want to defeat them – they can drop Rupees, Hearts, and other rare treasures!
Anyhow, go along to the steep incline. For this, dash to the top; otherwise, you’ll slide back down. You’ll soon come to some vines. Ascend them and go to the ledge to find another Red Rupee in the chest.
Go down and along the path. Dash to the high ledge and defeat the enemies you’ll find in the next area.
Further along, you’ll find a ledge with some grass on. Look around, as there is a hole in the base of the wall. When you find it, go through and along the path to forty Rupees . Exit the hole and head to the cavern’s exit nearby.
Back outside, utilize the nearby Bird Statue and go along the linear path. Soon enough, you’ll find Zelda. After the scene, go further along the path to find your Loftwing, imprisoned by the wooden boards! Go to your Loftwing’s confines and cut down the ropes fastening the boards to the wall.
Your Loftwing will soon be freed! This time, Zelda will have you jump off the ledge, without pushing you, and then you’ll summon your Loftwing. To do so, press Down on the D-Pad when you have control when falling. You’ll then learn how to control the Loftwing.
Basically, the Wii Remote is like the Loftwing, to a point. The A button will have you do a charge/tackle. Down makes you drop off. You can slow down with B. Swing the Wii Remote up and down to repeatedly flap and gain altitude, and then you can do a semi-nosedive to gain speed.
After getting acquainted with your Loftwing, you and Zelda will head back to Skyloft. Zelda will leave for a few moments, and, soon following, Groose and his gang will torment you a bit longer before the Wing Ceremony.