Do you need WiFi for Animal Crossing?

First, you need to have a friend code. (And the person you are trying to connect to needs one, also.) You do this by talking to the dog on the right side of the gate. He will ask what you want to do and you should say Friend Codes, and if you can't then say I wanna go out! or invite guests and then Wi-Fi. He will give you a friend code if you have the correct connections and stuff. Then, if you want to go to your friend's house and their gate is open, (using Wi-Fi) then say i wanna go out! then go to wi-Fi.