By default, members of a shared folder have edit permissions—they can can add, edit, or delete files. Sometimes you may want to let people view the files in your folder without being able to change them. Dropbox offers two ways to do this
You cannot download the entire folder without adding it to your Dropbox first. Since you said the folder is too large for your Dropbox, you will need to download every individual item separately like you would download any other file from the Internet (right-click the item, then Save Link/Target As...).