How do you connect to wi-fi on Animal Crossing

ok, well, first u need a wireless adapter. After that, you go on your ds (while you are in the same house as the adapter) and press the wifi settings. choose the wifi settings on the left and choose your wireless adapter from there. if the connection test works, u can now use wifi ^^ Statement: I want to know how to. But I don't think I have a wireless adapter. Do you have to buy it? I tried changing my settings and stuff but I think its because of the adapter thing. Ack this is sooo confusing. Why cant Animal Crossing be easier? x.x
EDIT:
Yes, you do need to buy it. However, what you are using may be what you need. Where you use the internet, you will be connected by either a dial up modem, cable or wireless signal. If you are using wireless, then you may use this to connect to Wi-fi. Beyond that I can't help you, as I don't know what type of internet or modem you have.