To your computer? That's copying, not printing. Just find the document (in the phone - it should appear as another drive) and drag it to where you want it.
To your printer? First set the printer (in the computer) to allow sharing. Then install Cloud Print (there are others, but I've been using Cloud Print for years, and it just works) set it up (it should find the printer if the computer and the phone are on the same wifi LAN), then just share a document with Cloud Print and it will print.