I need a solution like those of MS Windows 3.x and MS DOS, where you boot up the computer using DOS and if you want the GUI you just type the command
I need something like that with Ubuntu Server and any GUI environment. In other words, I need the computer boot up by default using Ubuntu server and works using the shell and if needed a GUI to do some tasks visually, I just type a command to load the GUI and then I could able to close (release resources used by GUI) it while the server shell still works.
Indeed, my first experience with Ubuntu was Ubuntu Server, from many years, but when I followed advises such as
sudo apt-get install ubuntu-desktop, I always finished with a computer boots up the GUI by default and I don't want that. I need GUI on demand. Even editing
grub will lead to need to reboot again.
I ask this question because I need to safe resources using the Ubuntu Server, but I need the ease of GUI during make major settings, such as, settings network, editing config files, etc.