When you're finished looking around for the first time, you can log out to quit your session.
When you log out, you'll be returned to the opening screen you found when your system started.
To log out, just go to the K-menu footprint on the panel, left- click once and click on Log out.
You'll be presented with a box asking you whether you want to log out. Click once on Yes.
After a few moments, you'll be returned to the log in screen.
At Login - type root
At Password - type your root password
To quit - Left-click on the K-menu, then
click on Log out, click Yes.