1. Open the Exchange management shell
Click on start and then expand Exchange Server 2016 and click on Exchange Management shell.
2. Enter the following command
Type in the following command to create your DAG: New-DatabaseAvailabilityGroup -Name DAG01 -WitnessServer DC2019 -WitnessDirectory C:\DAG01 -DatabaseAvailabilityGroupIpAddresses 10.0.1.14