RPi Zero W

How should I enable the wifi as this device does not have an ethernet socket?
I’m sure there is a way to set this up completely headless by modifying setup files but I was unable to do it with wpa_supplicant so I wanted to ask anyway.

Sorry for the late reply.

Check out dietpi-wifi.txt from the FAT partition that should pop up on Windows after flashing the image. If you don’t use EAP, then then just fill the following two: