Yes, you can use MemberMouse to sell content or access to content (for example, courses) individually as a bundle (add-on), as well as include them as part of a membership level. To do this, simply protect the page or post with the content you would like to make accessible by granting access to both the membership level and the bundle you would like to add the content to.
If you want this content to be downloadable, we recommend employing a plugin that specializes in file download protection. There are a number of file download protection plugins and WordPress Download Manager (http://wordpress.org/plugins/download-manager/) is one we've seen our customers use. By using a plugin like this, you'll be able to upload files and create download links.
To protect embedded video content, you would need to utilize the tools supplied by the site that hosts your videos (Wistia, Vimeo, YouTube etc.)
To learn more about protecting content, view our video on how to Protect and Schedule Content.