Ranger,

The "media pool" is simply the term used to name the built-in file browser in the Magix video programs. In editing mode (and the standard layout) you can find this in the upper, right-hand part of the screen. You've probably already used it without being aware of the name. It's really just a file browser to locate the media you want to use (video files, audio files, still pictures) on your system and import them into your arrangement.

I hope this helps to clarify the issue.