I've recently moved in to a new office who gets its internet through wired ports dotted around the room. I want to move them wireless but want to check which equipment would be useful before I start spending money!

If I buy a high-quality wireless router, can I plug the internet directly in to it and share it amongst everyone in the office? With the same router allow access to a printer plugged in to the router as well as access to a NAS device? 

Any suggestions as to the best