No, you do not need to have anything else. If you go to a hotel, they will probably have Free WiFi there. But coolest225 is right, you don't get internet just anywhere.
My Laptop Has Built-in Wireless Network Adapter. Do I Need Anything Else To Use It Away From Home?
You will also need a nearby wireless router. You can not use it in the moddle of nowhere.
Sure, you need to find the AP, if you beyond the range of ap, you can not connect to internet normally.