However, please be aware that (on modern Linuxen) the contents of /etc/nsswitch.conf dictate what name services are used (DNS, LDAP, etc) and in what order. Say fgrep hosts: /etc/nsswitch.conf. If it only references DNS, /etc/resolv.conf is the right place to look for your nameservers.
What Is Cloudflare's 1.1.1.1 DNS and How to Set It Up Apr 12, 2018 How to configure Dnsmasq caching DNS server in Linux Dec 13, 2019 Get Started | Public DNS | Google Developers Jun 25, 2020
How to Setup a local DNS Caching Server on Linux? - Geekflare
How To Look Up DNS on a Linux and Unix Systems - nixCraft Jan 12, 2015 Free and Public DNS Server List (Valid July 2020)
Build your own DNS name server on Linux | Opensource.com
Jun 21, 2018 DNS Servers: What Are They and Why Are They Used?