Turn on Wi-Fi on your Mac
On your Mac, click the Wi-Fi status menu in the menu bar, then turn Wi-Fi on or off.
To connect to a Wi-Fi network, click the Wi-Fi status menu , then choose the network, or choose Other Network, then choose a network. (If the network is hidden, scroll to the bottom of the list of Other Networks, choose Other, enter the network name and password, then click Join.)