The number of side quests in "Double Shadow Wonderland" is very large, and the kite branch is one of them. If you want to do this side quest, you can go to the Venom Roller of the Final Dawn in Chapter 4. After walking through a bunch of rollers, the main line will be in the small window on the left.
Where to make the double shadow wonderland kite branch line
Kite
Position: Chapter 4 The Final Dawn Venom Roller
After walking through a bunch of rollers, go straight to the small window on the left, and then walk straight through the roller to be the entrance to the branch line.
