As far as I know, some N300 series PDAs have a built-in Wi-Fi card. If this is your case, gather your Wi-Fi router's (or the one you want to connect your PDA to) SSID and encryption informations, go to 'Start > Settings > Connections tab > Wi-Fi' and tap 'Search for Networks'. After a while, the available WLAN should appear on screen. Select yours, fill in the required informations, and, after a while it should get connected. Otherwise (i.e., if your PDA is not Wi-Fi enabled), you will still be able to connect to the internet whenever it is connected to your PC (which should be on-line, of course).
Anyway, if you happens to miss your device's user guide, feel free to download it from
this location.
Just my 2 cents...
Regards,
Carlos