You need either a wireless-access-point-cum-broadband-switch-router (ADSL or cable) or the addition of a wifi switch / access point to work with an existing broadband switch / router. Obviously you'll need a broadband service connection to your home.
Alternatively, dispensing with a fixed broadband service, a 3g / 4g capable device to connect to your laptop (USB or similar), or a laptop with built-in 3g / 4g card. With either of these you'll need to subscribe to a mobile service provider.
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