Open Server Manager, expand the server you want to add a conditional forwarder, right-click Conditional Forwarders and click New Conditional Forwarder.
Specify the domain you want to create a conditional forward for, and click OK.
if you receive this “DNS the server with this IP is not authoritative” and you know that the server is authoritative for this domain, then ignore it. You are seeing this error message is that the machine wants to perform a reverse resolution, it fails because there is no PTR record populated for the IP address entered.
You can do the same with PowerShell
Add-DnsServerConditionalForwarderZone -Name "kandz.local" -MasterServers 192.168.122.42 -PassThru
use the parameter -ReplicationScope “Forest” if you want to create an Active Directory-integrated conditional forwarder