Commands can be typed in your Console. There are 2 ways to open your Console.
1. On the bottom, on the left, you find several icons. When you hover over them there will be a small pop-up explaining what it does.. The icon that looks like a piece of paper with text and a blue frame around it, is the one for your Console.
Click the console icon and within your interface, near the bottom, your console will open.Below it is a bar where you can type commands. In the top right corner of the console you will find a button to 'clear' it.
2. Menu above: View > Console
"help commands" gives a list of most of the commands.
CLICK HERE for more details on how to use these commands.