Even though your laptop or computer has a wireless network card it does mean that you magically get the Internet. You must in the close enough to a wireless access point to receive a signal.
Most common wireless Wifi hotspots have a limited distance of around 100-200 feet. There are other systems that can go a longer distance but in general this is a good point of reference.
You may need an access code to use any public wireless system. So you may need to get the access code from the supplier of the wireless Wifi hotspot.
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