The quest "My Kingdom for Scroll" is one of the many quests you can find in Disney Dreamlight Valley. This one is about searching for Scrooge McDuck's locked chest.
How to find Scrooge McDuck's locked chest in Disney Dreamlight Valley
There are plenty of familiar faces you'll run into at Disney Dreamlight Valley. Some of them will need to be unlocked before you can interact with them while others will need to be saved in certain places.
That said, the very first character you will meet in the game is Scrooge McDuck who is in the valley. After a short conversation with him, he will give you some tasks so that he can rebuild his shop.
Eventually you will receive a quest called "My Kingdom for Scroll" from Mother Grothel. In this mission, you must search for McDuck's locked chest.