Use the General tab to set a name and optional ID for your grid.
The name is not actually shown anywhere on your website. It just makes it easier for you to remember what this particular grid is for.
The ID is completely optional and will be used in the shortcode instead of just a number if you have one set. It basically just makes your shortcodes easier to identify:
[wpupg-grid-with-filters id="123"]
[wpupg-grid-with-filters id="photos-grid"]