Store can mean a few different things:

1. A place where goods are sold. A grocery store sells food, a clothing store sells shirts and pants, and a bookstore sells books. Some stores are small shops run by one family, while others are huge buildings with thousands of items for sale.
2. To keep something safe for later use. Squirrels store nuts for winter. Families store holiday decorations in the attic between celebrations. Your computer stores files and photos on its hard drive. This meaning connects to the idea of keeping a supply ready: a storehouse is a building where goods are kept, and someone might keep a store of canned food in the pantry for emergencies.

When someone says “what's in store for us,” they're asking what's coming in the future, like wondering what adventures or challenges lie ahead. And if you set great store by something, you value it highly. A coach might set great store by hard work and teamwork, meaning those qualities really matter to her.