This might not be a Windows 8 problem.
Are you able to connect to other Internet sites? Like Google, MSN or Yahoo?
Does your modem or router indicate a valid connection? Has this ever happlended before with you older computer?
If you can not resolve this problem with reasonable effort, you inform the vendor or store that you are having trouble.
Here is why I say this. Once in awhile new computers fail after several hours of use. It just happens. It is too to expensive to do 100% quality control. That is why stores have return policies. You may have to return the item and get a full refund.
Some advice. Never admit that you might have done something wrong.You didn't . Computer systems sold to consumers are almost fool-proof. It is not your fault.
Hope you get it resolved.