Make sure that there's a wireless card installed in the laptop. if it has, check that it's installed properly on device manager. if it's installed properly check if the wireless capability of the router is enabled. you can access the router's web user interface for you wireless settings. if you have done evrything but your laptop won't still connect, try to isolate the problem by connecting another laptop to your router wirelessly, if another will connect porperly to the router, it means that there's somethign wrong with your laptop or the other way around

hope this'll help you and just ask me if you have other concern

ciao!