Where do I delete my Lightroom CC Photos?

Ah! Finally! Thank you, this helped and doing via the web was much faster than the desktop app. I am not a professional user, rather a really new newbie learning my way around this complicated Adobe world, and dealing with all my storage being taken up before I even learn the app was a little frustrating, but now I know! I don't want to put all my pictures into CC or Lightroom, that's just way too much, I prefer to be more selective and I'm already paying you and others for storage, so it would be nice if this were a more obvious or streamlined process. In any case, thank you!

This raises a valid point. I have now actually stopped using Creative Cloud to hold my photos. The reason is that if I have all my images in Creative Cloud and then sync them all with Lightroom CC then the space required doubles. Why?? If the images are already in the cloud (Adobe's Cloud) then why are the files physically duplicated.?