If you only have access to the Google Earth website (earth.google.com), you can still view these files.
1. Go to earth.google.com
2. After it loads, click on the Projects icon on the left of the screen. It looks like a pin symbol.
3. Click Open, then click "Import KML file from computer"
4. Select the Beam Footprint file you have, then click Open. The beam's contours should show up on the map after that.
This also applies to users of the Google Earth mobile app (specifically iOS users), and the instructions are pretty much the same for that as well.