We have an SharePoint Foundation 2013 setup.
At the home page quick launch bar, we have 20 odd subsites, with other subsites off these.
Can I force SharePoint to keep this quick launch bar visible on all sites and subsites?
SharePoint Server Publishing features not available in SharePoint 2013 Foundation.need to deploy SharePoint Foundation 2013 Publishing Infrastructure solution in SharePoint foundation (more details fallow this link https://spf2013publishing.codeplex.com/) after deploying it, you need to activate SharePoint Foundation Publishing Infrastructure feature from Site Collection Features and Manage site features in SharePoint site's settings. After that you will have NAVIGATION option in your site settings under Look & Feel.