Internet not working when I changed Router DNS to RPi(3b+) DNS

[jfb]

@hotheadhacker

Do I need to disable my routers DHCP server to prevent this behaviour or is there anything else?

You need to change the router DHCP so that it provides the Pi-hole IP.

If you cannot do this on your router, then disable DHCP on the router and enable DHCP in Pi-hole.

How do I use Pi-hole's built in DHCP server (and why would I want to)?

Using Your Existing Router For Network-wide Ad Blocking You might not need to use Pi-hole's DHCP server: In many home environments, your router also functions as your DHCP server. In this case, you can often set Pi-hole to be the DNS server for your network clients in the router's DHCP (or LAN) settings page, which allows all of your network clients to block ads simply by connecting to the network. Setting it up this way is also what makes Pi-hole very powerful for network-wide ad blocking. …