When you upload files to a course, you can enable download on each type of content in your library. If the download option is disabled, members will only be able to view the content in your community and won't have the option to download it.
How to enable download on uploaded library content.
1. Click on the admin button
2. Click on courses in the admin panel menu
3. Create new content or enable downloads on existing courses by clicking the 3 dot menu and clicking the edit option on the drop-down
4. Find the General Settings section and select Enable downloads
5. Click save to enable the downloads option on your course.