Overview
In this guide I will show you how to connect your raspberry pi to a WiFi network without connecting a keyboard, mouse, or monitor. In order to connect it to WiFi you will need to add a file to the SD card with Raspbian OS installed on it.
Load SD Card on Computer
First you will need to plug in your micro sd card with Raspbian OS installed on it.
Create wpa_supplicant.conf File on SD card
Next go ahead and open the SD card on your computer and create a new file in the root directory called wpa_supplicant.conf.
Edit wpa_supplicant.conf with Network Credentials
Open wpa_supplicant.conf with a text editor of your choice to change the contents.
Add the following to the wpa_supplicant.conf file and change the ‘ssid’, ‘psk’ and ‘country’ to match your own network. If you are in the United States, the country code would be US for example.
ctrl_interface=DIR=/var/run/wpa_supplicant GROUP=netdev
update_config=1
country=<Insert 2 letter ISO 3166-1 country code here>
network={
ssid="<Name of your wireless LAN>"
psk="<Password for your wireless LAN>"
}Finally, save the file and unmount your SD card.