Android supports Private DNS, which uses DNS over TLS to secure your queries.
Host name for 9.9.9.9 Quad9 DNS on Android
If your device runs last versions of Android, here is the method to set up 9.9.9.9 DNS host name of Quad9.
Steps to configure your Android device to use 9.9.9.9.
Go to Settings → Connections → More connection settings → Private DNS. Select the Private DNS provider hostname option. Enter dns.quad9.net and hit Save.