Check that is is working via Ethernet. You could be having DNS resolution problems. Depending upon your ISP you have to set your router up with the PPPoE username and password. Or, if you have been issued a static IP address by your provider, (you would need to have requested it), the static IP fields (including network mask and gateway) or clone the Mac (nothing to do with Apple Computers) address of your computer given to you by the provider must also be set in the router.
Once you can confirm connection via Ethernet you can set up your wireless network (seems like you know how to do that part).
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