If you have downloaded Pages on your Apple ID before, the "Purchased" trick won't work because the app isn't in your history. You can fix this using a friend's device or a newer Mac/iPhone.

If you still want to use a third-party website, make sure to:

If you have previously "purchased" (even for free) Pages with your Apple ID, follow these steps:

For very old Macs (running macOS 10.12 or earlier), you may need the standalone iWork '09 suite. Apple used to distribute these via physical discs or