There are two types of wifi control:

• STA mode: The car is a client for your wifi network, that means you have to connect it (using the code) to the wifi. Unfortunately, this method is inapplicable since the Luther wifi does not allow client connection without administration
• AP mode: The car becomes a wifi hotspot itself, and sends out signals that can be used to control its movements (it does not, sadly, have internet access). The IP address of this wifi module is 192.168.4.1

Follow the guide on the official website: https://osoyoo.com/2020/10/30/sg90-servo-steering-robot-car-lesson-5-wifi-udp/ (opens in a new tab)

Download this code and open it in your Arduino IDE, connect it to your Arduino and upload it: https://gist.github.com/minhviet0308/a35648f16f9a2d826a88babe2beeede2 (opens in a new tab)