HOW TO GET INTERNET SERVICE ON AN IPOD TOUCH LIKE AN IPHONE?

So i have a wireless router at home and make use of it for my ipod hold but how can i get internet similar to an iphone. Like when i go in the car and you do not need wi-fi similar to an iphone. So is there something i can do it similar to an iphone.
For example, a little people get these wi-fi thingies for their laptop but the do not need wi-fi, only the label thing which helps you stay connected.