You should first check to see if the Wi-Fi is on. Select Wi-Fi in the settings list and if it is off, drag the switch to the right and it should turn orange. If the Wi-Fi is already on, you should try moving closer to the source in order to obtain a better signal, and if that connection is still not working, you may be connected to the wrong network. Select Wi-Fi under the settings menu, a list of networks should appear, and select the network that you are trying to connect to. I recommend you also look through the [[Nokia Lumia 521 Troubleshooting|troubleshooting guide.]]