iWork isn't usable nor is Pages on my MacBook Pro which is crazy, what is a compatible Office Suite to use?

Let's stop calling it iWork as Apple dropped that trademark name when they retired the iWork '09 office suite in Fall 2013. The applications are referred to now by their name and a version number (e.g. Pages v11.1, Pages v12.1, etc.).

If you have ever installed Pages on an older Mac, you can get the last version of it (v11.1) installed on macOS Catalina, provided you are signed into the Mac App Store on Catalina with the same Apple ID. Do that, and then press cmd+0 (zero) to open the Purchased panel. If Pages appears there with a blue outlined cloud, click that icon and a dialog will appear asking you if you want to install the last compatible version of Pages for Catalina.

Pages v11.2 and later do presently require macOS Big Sur (11.*) or later.

Pages, Numbers, and Keynote are perfectly usable on Catalina and you can get the last compatible versions for this operating system through the Mac App Store. Apple is moving on, as their three-year sliding window of operating system security and browser updates would suggest. When they add features to Pages, Numbers, and Keynote that are not available in older operating systems, that isn't Apple attempting to make you purchase a new/er Mac. That is entirely up to you and your budgetary planning process.

Another commercial MS Office compatible Office suite to trial and potentially purchase is Softmaker's Office 2021 for Mac. More like the MS Office interface with native Office document handling. LibreOffice may be free, but you will pay for it in learning curve.

LibreOffice is very good and will run on macOS 10.12 or newer. See: https://www.libreoffice.org