Sub location Is designed for brands and businesses that have more than a single location.

Example:
Joe’s flower has one location In LA and another location in Santa Monica
Each location has its own properties such as on Google my business, Yelp Facebook page etc.

In this case, Joe will need to have 2 review URLs under the same brand so each location can generate reviews while everything is going to feed into one place to manage it all.

Do you set up your sub-location go to:
Location settings >  Sub Locations
Click Add Sub Location
Follow the instructions in this video below