If you can’t connect to a Wi-Fi network on Mac
If you’re having problems connecting to a Wi-Fi network, there are several solutions you can try.
Make sure Wi-Fi is turned on. You can use the Wi-Fi status icon in the menu bar to turn Wi-Fi on.
You may be out of range. Make sure your Mac is within range of the wireless network.
The Wi-Fi service may not be available in Network preferences.
On your Mac, choose Apple menu > System Preferences, then click Network.
If Wi-Fi isn’t in the list of network connection services, click the Add button at the bottom of the list, click the Interface pop-up menu, then choose Wi-Fi. Name the Wi-Fi service, then click Create.
If you are connecting to a wireless network created by an AirPort base station or AirPort Time Capsule, restart the device by unplugging the power cord. Wait a few minutes, then plug the power cord back in. After the network is available, try connecting again.