Yes, you can move icons around to different pages, and yes you can create folders and move icons into folders. But you can't add new pages beyond the original 7 that HTC Sense provides. There are other home launcher apps on the market, and some may allow more pages. Not sure. I like Sense, so I stick with it.
One thing you CAN do is create different "Scenes", which is basically a whole new set of 7 pages of icons. Think of them as different ways you would setup your phone, like you can have a "Work" scene, then a "Play" scene, etc. I haven't used scenes much yet, but could come in handy.
Hope this helps!