How to setup DNS

I have a network like this:

1) Client machines point at DNS on Windows Primary Domain controller.  Need to point at Primary so sees domain machines.  Use DHCP server to set the DNS IP of the domain controller.

2) On the Primary domain controller I set the forwarder on the DNS server to 1.1.1.1.

My questions is should I set to the IP of Firewalla Gold or 1.1.1.1?  I want to use DNS over HTTP.