Save Documents in Microsoft Office 2016 for Mac
You can save a file to a location on your computer, like a hard disk drive or a flash drive, or on an online service, like OneDrive. You can also export files to different file formats and save them to different file names.
Save a file
Save as a different file name
Save to a different location on your computer
Save to a different location on an online service
Save as a different file format
Save AutoRecover information automatically
IMPORTANT: Even if you have AutoRecover enabled, you should save a file frequently while you are working on it to avoid losing data due to an unexpected power failure or some other problem.
Save Documents in Microsoft Office
Site Credit: Save files in Word 2016 for Mac