Help -> 2 Arduino Mega + HLK-RM04 (Wifi Shield) + Ping sensor + RGB LED


Currently i am working on a school project.

At the moment i have the following hardware:

2x Arduino Mega + HLK-RM04 Wifi Shield
Multiple Ultrasonic Ping sensors
Rgb Led strips (+ controller)

1x Arduinon Yun

The goal is to send and receive data between multiple arduino boards over Wifi, i want to use the Yun to serve a HTML page to start the actions on the Aruino’s.

I have added a simple diagram as example.
(See the attach)

At this moment all the Arduino’s are connected to the same Wifi SSID. But i dont know how to get started on the communication part over Wifi.
I want to be able to send the sensor information from one arduino to the other and start the led strips remotely.

Can someone help me to get started and point me in the right direction?

Thanks in advance!