Bearded Anarchy My answer of your question is already in my previous comment :)
If you're using Adguard on your Windows OS then open Adguard > Settings > DNS.
Scroll down and add DNS
If you're using TLS then type TLS:// and enter your nextdns TLS link mentioned in your nextdns.
If you're using https then use nextdns https:// link
Save it and then enable DNS and choose your saved nextdns.
Similarly you can do for Android or iPhone.
Here's the screenshot of my Android Adguard with nextdns.
I set RM to recognise/name my device on Nextdns server to monitor filters.
I hope you found this helpful.
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