You need a modem with an Ethernet connection, not USB. You also need a cable router, not ADSL. The modem plugs into the WAN socket of the cable router with an Ethernet cable. You should then plug the PC into one of the router's LAN sockets until you have established your Internet connection and entered your Broadband user name and password. Once you have this set up and working you can set up the wireless side of things and disconnect the PCs Ethernet cable.