Install Microsoft Word on a Mac Pro by running the installer for Office 365. A Microsoft account and an active Office 365 subscription are necessary to run Microsoft Word on a Mac Pro.
To download the installer, log into your Microsoft account at Office.com, click My Account, and then click the red Install button under your Office 365 subscription. Then click Install under Install Information, and open Finder once the download finishes. Navigate to the Downloads folder from the list on the left, and run the installer package. The exact name of the file may differ depending on the version you download.
When the installer launches, click Continue, provide the credentials to your administrator account, and click the blue Install Software button. Once the installation is complete, the Mac Pro opens a window to help with the activation. Click Get Started, sign into your Microsoft account, and click Start Using Word. You can find Microsoft Word under the Applications folder by using Finder.
You must have an active Office 365 subscription in order to use Microsoft Word. Once on the Products page, click For Home or For Business, depending on your needs. Select a payment plan, click Buy Now, and follow the instructions. Microsoft offers both monthly and annual subscription plans.
It's also possible to try Microsoft Word for free for a month. To do so, click the Free Trial button on Office.com, and then click Try For Free. Although Microsoft asks for payment information to grant the free trial, the company does not charge you until the trial ends. You can cancel the subscription at any time to make sure you don't have to pay when the trial ends. Canceling the subscription does not end the free trial.