downloading Pages App
I need an older version of the Pages App, the current version is 13 and my Mac only goes up to 10.17
iMac 27″, macOS 10.15
If you installed Pages previously using an Apple ID, you can get Pages v11.1 which is the last compatible version for macOS Catalina 10.15.7. If you never installed Pages because it was preinstalled on your Mac, either by Apple, or a reseller, then you cannot get older versions of Pages.
Launch the Mac App Store and sign in with the same Apple ID that you used to install Pages previously. Press cmd+0 (zero) to open the Purchased panel. If Pages appears there with some form of download/update indicator, click that. Do not click Cancel on any dialogs and the final dialog should offer to install the last compatible version of Pages for macOS Catalina.
Sometimes, it will resist installing the compatible version if you have a much older version of Pages installed. Assuring that you have that on a Time Machine backup, you can then move that older version to the Trash, empty the Trash, and then perform the second paragraph again.