What version of Opera?
There is no Opera Link for Opera Blink (Opera 15+). You can enable Sync on opera:flags, but note that it's still experimental and only Speed Dial, Stash and Custom Searches are available atm.
Opera Blink also doesn't have a way to import bookmarks from other browsers. A possible workaround is to import them into Chrome and then copy bookmarks*.* from Chrome's profile folder to Opera's one.