The Shaw Gateway provides TV services within your home, not Internet services.
The two IP-addresses connect into the WAN side of your Shaw Router. The router "consumes" one, to be a "proxy" for all your wireless devices on your private network. If you login to the web-interface of the Router, you can designate one of the LAN ports on the Router to consume the other IP-address. The other LAN port(s) on the Router connect, via Ethernet cable(s), to "wired" devices (Smart TV or computer or ..) to connect them into the same private network as your wireless devices.
