remove xorg

 sudo apt remove xorg

[sudo] password for dhwan: 

Reading package lists... Done

Building dependency tree... Done

Reading state information... Done

The following packages were automatically installed and are no longer required:

  libglu1-mesa libxcb-damage0 x11-apps x11-session-utils xbitmaps xinit

Use 'sudo apt autoremove' to remove them.

The following packages will be REMOVED:

  ubuntu-desktop ubuntu-desktop-minimal xorg

0 upgraded, 0 newly installed, 3 to remove and 1 not upgraded.

After this operation, 54.3 kB disk space will be freed.

Do you want to continue? [Y/n] y

(Reading database ... 187332 files and directories currently installed.)

Removing ubuntu-desktop (1.539) ...

Removing ubuntu-desktop-minimal (1.539) ...

Removing xorg (1:7.7+23ubuntu3) ...