Try parental control software and put only that website on the whitelist.
The alternative is to write your own browser based on the Chromium framework, leave out the address bar and only accept links that are to the same site.
Hi i know it sounds stupid but how do i forbid access to all internet websites exept one?I dont want anyone viruses and hackers and spying
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Chowhound
Comic Vine
GameFAQs
GameSpot
Giant Bomb
TechRepublic