Pages continues to crash

Once Pages crashes or hangs, it will continue to do so until you break that cycle. Press and hold the shift key while launching Pages to prevent it from reloading its previous application state (e.g. crashed/hung).

If it still crashes after the first paragraph, boot your Mac into Safe Boot mode by holding the shift key during boot. This will bring you to a sign-in screen, and you will know it is a safe boot, because those words appear in red. Once signed, in try Pages again to see if it crashes. If it does, press shift+command+G to bring up the FInder's Go To Folder dialog. Copy/paste the following path into the dialog and click GO.

~/Library/Contents

This will open a Finder window inside your local Caches folder. Press command+A to select all of the items inside this folder, and then right-click, selecting Move to Trash. Close the Finder window, and without emptying the Trash, reboot normally. Once you have rebooted, empty the Trash, and launch Pages (without the shift key) to see if it works normally.