Where is the auto save option in Microsoft Office 2016 for Word and Power Point?
This is not auto-save however.  This simply sets the interval at which Excel will generate an auto-save file should there be a crash.  If you close without saving, this file is immediately deleted.  If the crash doesn't meet Microsoft's definition of a crash, the file is deleted.  If you don't open Excel properly the next time, the auto-recover won't show and the file will be deleted.  

What most people want, myself included, is a true autosave.  Once you create a file, name it and save it once, it will continue to save it again at a set interval.  Microsoft does not offer this option.