Kali Linux use
GDM3 as a default Display Manager. First confirm that your Kali Linux is set to use
GDM3 as a default display manager:
# cat /etc/X11/default-display-manager /usr/sbin/gdm3
/etc/gdm3/daemon.conf configuration file and uncomment the following two lines:
AutomaticLoginEnable = true AutomaticLogin = root
Once you have made the above change simply
reboot your Kali Linux to confirm your configuration.