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

FAQs
2

Hi, I am trying to see if this works for two networks? I use DietPi (Pi-hole Version v3.1.4 Web Interface Version v3.1 FTL Version v2.10) However, I don't see anything in the gui where I can add DHCP service for 192.168.0.0/24 and 192.168.2.0/24.

Thanks