You can now get Office Add-ins from the Store or use Add-ins you already have from right within recent versions of Word for Mac and Excel for Mac.
If you're looking for a built-in add-in such as Solver or Analysis ToolPak, select the Tools menu and then select Add-ins.
Get an Office Store add-in for Word or Excel for Mac
On the Insert menu, select Add-ins.
To get new add-ins, select Store. To use add-ins you already have, select My Add-ins.
The add-ins you'll see will depend on the app you're using and the kind of Office 365 subscription you have.
Office 2016 for Mac and Office 2019 for Mac don't currently support organization-based add-ins.
Get a VBA add-in for Word or Excel for Mac
On the Tools menu, select Add-Ins.
In the Add-Ins available box, select the add-in you want, and then click OK.
Office Add-ins aren't available in Office for Mac 2011. They're only available in newer versions.