First create Ad hoc networkand connect two PC and one of two is connected to internet;  if you do not know to do that see the first step of how to share files/folders without cable on two desktop/laptop. and follow these steps.

 Go to Control Panel=>Network and Internet=>Network Connections
 To share an Internet connection with other devices, right-click on the Host’s wireless adapter icon. Go to Properties, click the Sharing tab, and select Allow other network users to connect through this computer’s Internet connection.
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Optional:In Settings you can select the network services the Client machine can access.then OK




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Now you can start browsing on both PC