The NetworkManager daemon attempts to make networking configuration and operation as painless and automatic as possible by managing the primary network connection and other network interfaces, like Ethernet, Wi-Fi, and Mobile Broadband devices.

change DNS tyep and nameservers

Ref

# change DNS type
sed -i 's/^dns=.*$/dns=default/' /etc/NetworkManager/NetworkManager.conf

# or possiblty you can create a conf to override in /etc/NetworkManager/conf.d

# change default servsers (set after each restarting NetworkManager)
nmcli connection modify <connection_name> ipv4.dns <dns_server1> <dns_server2>

# restart NetworkManager and check the /etc/resolv.conf is what you want
sudo systemctl restart NetworkManager