Managers can share files with members in two ways: 

If the file is 25MB or less, it can be attached directly to a post from your computer and will be available for download from an email. 

For larger files, they would need to first be uploaded to the Resource Center prior to being added to a post.

Files Stored in the Group's File Section

Click the Upload File icon, select From Resources, choose the file, and click the Add button.

To attach files from your computer, click on the Upload File icon, select From Drive, then either drag and drop the file or click the box to choose the file.

To attach multiple files from your computer, hold down the Command⌘ (Mac) or Control (PC) key and select the files to upload.