What is Site Setup?
From EdTech Help
The Site Setup tool provides information about the sites to which you currently belong or may join. If you have a role that allows it, you can use this tool to make changes to information about the site, tools available in the site, and access to the site. You can also publish the site using the Site Setup tool.
Many of the functions of the Site Setup tool mirror those of the Site Info tool; Site Setup is available through Home, whereas Site Info is available in each site.
If you don't have the appropriate permissions, you will only see the information about the site published by the site owner in Site Setup.