Quick connect is a feature that lets you initiate a connection to a computer from Nearby and Remote Computers list without having to create a new saved screen.
Screens for macOS
You can simply double-click the computer name to establish a one-time connection. Screens will prompt for log-in credentials for a valid user account on the destination computer:
Screens for iOS
Tap the + button and select New Screen:
Once the Nearby and Remote Computers list appears, tap the (i) button from an item in order to establish a one-time connection. Screens will prompt for log-in credentials for a valid user account on the destination computer.