Click the Publish button under “Course Status” in the upper right hand corner of the page. Students cannot see your course and content until you publish it.
Content areas in Glow can be made to be available or unavailable to students even after a course is published. To the right of modules, pages, or other content will be a publish/unpublish icon. If the icon is a light grey circle, then the content is unavailable to students. You can click on the icon to toggle the availability. When the circle is green with the check mark, the content item will be available to students.
In the case of modules, you will want to make sure that the parent module is available to students as well as the content items listed in that module. Both the icon for the parent module and the content items in the module will need to be the color green.
You can use Settings > Navigation to hide menu items from students including the Files menu item. When students view the course, the Files menu item would not be present. This effectively hides all the files in the file repository. You could then selectively share files by linking to files from a page or module.
However, there is also the option of keeping the Files menu item accessible to students, but controlling what students can see or access. For more information about it, refer to this documentation.
Once you have uploaded content and made it available or unavailable to students, you can check on your work using the Student View button on the right side of the Course Home Page. This will allow you to explore the course and see the course as it will appear to students. Click on the File menu item and test the accessibility of the files there. Also look at any modules or pages you have added and see if you can see them. To exit student view, there is a button in the lower right hand corner that says "leave student view."