In Legend of Zelda Skyward Sword HD, there are occasions that require you to find the Knight Commander. One of them is at the beginning of the game, and the other during a side mission. In Skyward Sword HD, the Knight Commander will be in the same position at all points in the game. Specifically, you can find him in Sparring Hall on Skyloft.
The Sparring Hall is right next to the Knight Academy. This is the building where you start the game. If you are still a bit confused, use the minus button to check your map. There are two points in the game where you must find the Knight Commander.
The first is at the beginning of the game, when you are trying to find the Link’s missing Loftwing. The knight commander will provide you with a practice sword, so you must find it in the training hall to get it. He will also teach you how to use the sword at any time in the game, so if you need any advice, you can talk to him there.
The second time you must find him is in the Hot Pumpkin Soup side quest. To start this mission, go to Pumpkin Landing, a large floating island in the sky shaped like a pumpkin. Enter the building on the second floor and roll a few times on the balcony. The chandelier will shake and eventually collapse.
The owner will be very upset and will make you work hard to pay for the loss. The first thing you should do for him is to give the Knight Commander a bottle of pumpkin soup, but it must be warm. This means you must take it away in less than five minutes. Fortunately, we now know where he is. Fly back to Skyloft and head to the Sparring Hall where the Knight Commander is waiting.