Setup WiFi With Command Line.

Edit /etc/wpa_supplicant/wpa_supplicant.conf file.

ctrl_interface=DIR=/var/run/wpa_supplicant GROUP=netdev
update_config=1

network={
        ssid="MY-WIFI"
        psk="password"
        key_mgmt=WPA-PSK
        priority=1
}

Refer: https://www.raspberrypi.com.tw/2152/setting-up-wifi-with-the-command-line/