...
Your store should be running on Magento 2 Community Edition version 2.1.x.
...
How does it work
In order to start using the SMS Marketing extension, you need to do some configuration by going to Stores > SMS Marketing.
There are
At Gallery tab, click on Add New button to create a new Gallery.
Admin will be able to enter the necessary information for the Gallery as: name, status, and url.
...