Oppo
Set Up Private DNS auf Oppo
Private DNS encrypts the lookup step that translates a website address into an IP address. Without it, that request travels in plain text to whichever DNS server your mobile network or Wi-Fi router assigns, usually your carrier's own server.
On Coloros, this option sits under Settings ➔ Connection & sharing ➔ Private DNS. From there you pick Automatic, which lets the system choose an encrypted DNS server if one is available, or Designated Private DNS Provider, where you type the hostname of a provider such as a public DNS service and tap Save.
Choosing the designated option gives you control over which company handles your DNS traffic instead of leaving it with your carrier by default. This matters most on public Wi-Fi, where an unencrypted DNS request can reveal browsing patterns to anyone else on the same network.
Private DNS only protects the address-lookup step, not the full content of your traffic. If an app already uses its own encrypted connection, switching this setting will not change much for that app. On networks that block outside DNS servers, such as some corporate or school Wi-Fi, an active private DNS entry can cause pages to fail to load until you switch back to automatic or off.