Firewall security and SQL Server
By putting only my IP address in the scope means I've blocked everyone else apart from me connecting to the remote database?


Correct.  


  Exceptions that you add to the firewall can restrict the opening of
  the port to incoming connections from specific computers or the local
  subnet. This restriction of the scope of the port opening can reduce
  how much your computer is exposed to malicious users, and is
  recommended.


https://docs.microsoft.com/en-us/sql/sql-server/install/configure-the-windows-firewall-to-allow-sql-server-access?view=sql-server-ver15#BKMK_additional_settings