Yes it can. If you set it up correctly it has the DHCP server turned off and has a different IP address then the main router, like main beiing 192.168.1.1 and the one you use as a WAP is 192.168.1.2, and you haven't used the WAN/Internet port on the second router. All you have to do is connec a device to one of the other LAN ports on the second router. It will then get an IP address from the DHCP server in the main router and the main routers IP addres as its Default Gateway and you'll be on the net.
If you have setup the second router as a ROUTER, IE used the WAN/Internet port, that can cause problems with double NAT and will block LAN/Network sharing from devices connected to the main router whether wired or wireless and the devices connected to the second router whether wired or wireless.