wireless access point (a wireless networking item)
That depends on what you are attempting to do. If you are trying to access the internet, then no, a wireless router is not needed.
Power up your router. Connect it wirelessly or though an ethernet cable. After that log on (how to that is described in the manual). Check setting for a DHCP server, make sure that it was set up...
IP address and mac address
A wireless access point can function as an access point and it can also be used as a repeater....