Use Pi-Hole with NGINX for HTTPS WebGUI Access
The default installation of Pi-Hole gives you an option to use the lighttpd webserver, which is a very lightweight webserver option, but it does not give you the option to enable or use HTTPS for accessing the WebGUI.
We can force the local Pi-Hole installation to use HTTPS with the help of NGINX.
Prerequisite
If you have already installed Pi-Hole on your system and chose to use lighttpd, run the following command to stop lighttpd and uninstall it:
#Stop lighttpd
sudo service lighttpd stop
#Stop lighttpd from starting at boot
sudo systemctl disable lighttpd