iWork for older OSXs

Open the Mac App Store & hold down the option key while clicking the Purchases tab on your Catalina Mac. If you see Pages, Numbers, and Keynote with Update/Install buttons, it may offer to download a previous version of these applications compatible with Catalina. If you have never installed a version of Pages since October 2013, there is no way to install a version older than what is currently available in the Mac App Store. Currently, macOS Monterey or Ventura is required.

In Mojave and later releases of macOS, one must enter ⌘+0 (zero) to get to the previous purchases panel in the Mac App Store. This changed from the option+Purchases tab in High Sierra and earlier.

iWork '09 is 32-bit & will not run on macOS Catalina or newer.

See VikingSOX's reply in this discussion in the Pages for Mac forum.

VikingOSX would know that. I don't have Catalina installed on any Mac to check. Follow the steps to install a previous version & it will install the appropriate version for Catalina if it offers a compatible version.