Let's add additional private and public IP addresses to an NIC.
First, you need to create a public IP address by running the following cmdlet:
$PIP = New-AzureRmPublicIpAddress -Name NewPIP -ResourceGroupName PacktPub -Location WestEurope -AllocationMethod Dynamic
Next, you add the desired public and private IP addresses with the following cmdlet:
New-AzureRmNetworkInterfaceIpConfig -Name AdditionalIPConfig-Subnet $Subnet -PrivateIpAddress 192.168.1.10 -PublicIpAddress $PIP