Master selection !! options: Arduino Due ch340 and Nextion HDMI.

Hello there. I will use 3 slave devices and masters in the project. I will check the input output of some data in the project with Nextion HMI screen. I have two choices for the main choice. One of them is Nextion NX8048K070_11C (ARM 108 MHz, ITEAD Wiki NX8048K070) and the other is Arduino Due-CH340 (https://store.arduino.cc/usa/ arduino-due). Which is easier to choose. How should I use a method as a communication protocol. I would be very pleased if there is a sample.

There is definitely not enough specification to decide on this. What is this system used for, what kind of software should run on it? Do you expect it to program using the Arduino IDE? What are the other 3 devices (slaves) and how do you plan to connect them?

I would like to check the engine groups with 3 (Slave) arduino nano. I'll be communicating the slave cards with a Master device and making some data exchanges. I will display the input and output data in these motor groups with Nextion HDMI. Some data entries will do on this screen.

I don't have enough information to decide on the choice of master. Nextion I can use HDMI Nextion Enhanced NX8048K070_011C as master( https://www.itead.cc/nextion-nx8048k070-011r-011c.html here features available).
The other option is the Arduino Due ch340 ( https://store.arduino.cc/usa/arduino-due features here ). To master you should choose which one.

Can you give an idea about communication? how should I follow a path. I am very pleased if you can give an example.

thank you..

If this specification is complete (I doubt) you don't have a choice. You wrote you need a display. The Due doesn't have one in the configuration you linked to, so the only option you have seems to be the Nextion.