You already understand what it means to enforce a GPO, and how to do it inside GPMC. Now let's turn to PowerShell to enforce the link between MyNewGPO and the IT Department OU, in order to override the inherency blocking that is currently in place on that IT Department OU:

Set-GPLink -Name "MyNewGPO" -Target "ou=IT Department,dc=mydomain,dc=local" -Enforced Yes