Installation Steps
Install Ubuntu Server 20.04 (https://ubuntu.com/download/server)
Install Pi-Hole – sudo curl -sSL https://install.pi-hole.net | bash
Set the Web Admin Password – pihole -a -p [password]
Install Unbound DNS – sudo apt install unbound
Create Unbound Configuration File – sudo nano /etc/unbound/unbound.conf.d/pi-hole.conf
Copy example config – https://docs.pi-hole.net/guides/dns/unbound/
Restart Unbound to apply Configuration – sudo service unbound restart
Disable Forwarding DNS in PiHole
Set Custom DNS in PiHole – 127.0.0.1#5335