A family of Microsoft word processing software products for creating web, email, and print documents.
As Jordan indicated, in the Print dialog open the Copies & Pages dropdown then select Layout. Regarding the other portion of your inquiry, that choice pertains only to the current print job. The setting reverts to Single-Sided based on the Default Settings... IOW, you need to select Two-Sided each time you wan to invoke it unless you change the Default Settings for your printer.
Please disregard the screen shot provided by Phillip. The Print dialog differs depending on the program calling for the service as well as the options available for the printer being used. His screen shot is a totally different type of Print dialog & the one for Word includes no such check box.