Listing of files in /etc:
/etc/hostname
/etc/fstab
/etc/network
/etc/hosts
/etc/apt
/etc/sudoers
/etc/systemd
/etc/init.d
/etc/resolv.conf
/etc/profile
/etc/pacman.conf
/etc/ssh
/etc/xdg
Each directory and file listed here is a crucial part of the system configuration. Some of them contain configurations for networking, users, system services, and more. Explore and modify them only if you know what you're doing, or risk falling into the digital void.
For more help, refer to Help.