Explanation

Box 1: 8080
1433 is the default port, but we must change it as CONT_SQL3 must not communicate over the default ports.
Because port 1433 is the known standard for SQL Server, some organizations specify that the SQL Server port number should be changed to enhance security.
Box 2: SQL Server Configuration Manager
You can configure an instance of the SQL Server Database Engine to listen on a specific fixed port by using the SQL Server Configuration Manager.
References:
https://docs.microsoft.com/en-us/sql/database-engine/configure-windows/configure-a-server-to-listen-on-a-speci