Private DNS on Android uses your DoT custom URL.
These steps are for stock, or close to stock, Android. If you have a Samsung the steps are similar but if it's easier you can refer to these steps instead.

Go to Settings and find Network & internet

Screenshot showing how to get to network settings

Towards the bottom, choose Private DNS

Screenshot showing how to get to Private DNS setting

Put in your custom URL: {{valueIfPremium(dotUrl( user.username),user.premium)}}

Screenshot showing how to set custom DNS provider

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