It takes a special (and practiced!) kind of patience to move apps and folders around the various pages of the iPad.
All I can tell you is to keep trying; you have to hold the app/folder j-u-s-t right against the side of the screen before it will move. Again, it takes practice.
Or.
Activate the "wiggle" mode. Then, put the app or folder on your dock. After the item is on the dock, swipe to the page you want to place the app or folder. Once tat the page, move the app/folder off the dock onto the page. Aft that, press the round Home button to stop the icons from wiggling. And, you're done.
I like this method the best because you can move up to six apps/folders at a time (as many will fit on your dock). You can make room for moving items (on your dock) by moving them off, first, while in wiggle mode.
Hope this helps.
Marilyn