If you're using Windows, first thing you need to do is make sure that your hot keys are enabled. This is really easy to do. Go to your desktop, right click, go to Graphic Options, Hot Keys, then click enable. If this is already done, then it's easy to do. It's making sure those hot keys are enable before this shortcut works that makes it tricky. So once those are enabled, hold "Ctrl, "Alt," and press one of the directional arrows, and your screen will flip towards whichever arrow you press. If your screen is in normal view, and you press the up arrow, it will flip it upside down, and vise-versa. If your screen is in normal view and you click the arrow left or right, it will flip the screen sideways.
Based on my research, there is no automatic screen rotation for Mac, it has to be downloaded. You can rotate specific windows by holding "command," "shift," and then dragging the handle, but there is no keyboard shortcut to rotate the entire screen. Feel free to correct me if I'm wrong. I'm not a Mac user and was unable to find anything on this.