There’s only “Suspend” and “Do nothing” options for laptop close actions.
To have Ubuntu shutdown when the laptop lid is closed, edit the logind.conf file:
sudo vi /etc/systemd/logind.conf
Uncomment the line #HandleLidSwitch=suspend and change it to HandleLidSwitch=poweroff.
You can also change the value to HandleLidSwitch=hibernate to hibernate Ubuntu when lid is closed.
Restart the machine or issue the following command to apply the change:
sudo systemctl restart systemd-logind.service