To configure NextDNS, run the following command as root:
nextdns install -config <your_conf_id>
By default, nextdns listen on localhost only. To setup on a server,
add the -listen :53 option in order to listen on all interfaces.
Go on https://nextdns.io to create a custom configuration ID.
Then setup your DNS manually to 127.0.0.1 or by running as root:
nextdns activate