Processes in Microsoft 365 for setting up Office apps, redeeming product keys, and activating licenses.
While new Macs can run iOS apps, the iOS version of Office is woefully underpowered for anything but quick edits and on-the-go presenting.
The licenses for Microsoft 365 and newer retail versions of Office are platform-agnostic. You may be able to install your old version of Office on your Mac. Using your Mac, visit your Microsoft account Services & subscriptions page, find your version of Office and click on the Install link on the right side of the page. If the installer that is downloaded is a Mac installer, run it and you're good to go.