Claims Letters is made available to users via the Microsoft App Store. Some companies disable the app store for secuirty reasons, and rely on IT Administrators making specific Add-ins available to their users.
The recommened approach for deploying Add-ins is using centralized deployment method via the Microsoft 365 Admin center. This article from Microsoft explains in details the steps involved, or you can see this video which shows the steps involved.
There are some other methods of deployment that can be used for Add-ins, but our suggestion is to contact us to discuss the approach
Microsoft Word and Outlook Add-ins are easy to install, start Microsoft Word and click on "Insert > Get Add-Ins".
We are here if you need help, just contact us and we will help you through the process