Conclusion
Wireless interface not activated
Execute the instruction ifconfig wlan0 (replace wlan0 with the actual name of your wireless interface) to inspect if the interface is arranged accurately. If the interface is not set up correctly, input the instruction ifconfig wlan0 192.168.1.100 netmask 255.255.255.0 (replace with your intended IP address and netmask) to set up it. Kali Linux Fern Wifi Cracker No Wireless Interface Was Found