This add-in works in: Excel 2016 or later on Mac, Excel 2016 or later on Windows, Excel on the web, PowerPoint 2016 or later on Mac, PowerPoint 2016 or later on Windows, PowerPoint on the web, Word 2016 or later on Mac, Word 2016 or later on Windows, Word on the web.
If you don't have the above, try using Office Online.
Enable editing, trust the add-in and look for the add-in in the insert tab under 'My Add-ins'. Click here for step by step instructions
1. To find your add-ins, click on the 'Insert' tab in the top ribbon of your Office application.2. Click 'My Add-ins' to view your installed add-ins. On some versions of Microsoft Office, this button may read 'My Apps'.