Arduino and Nextion

[Jabmel]

hi all. Very interested in my next project to use a nextion touch screen to turn a relay bank on via arduino. Mega (after some logic)

Looking everywhere on line and you tube. Can find lots that have done it but can't find the code

In a nutshell.

Basic 1 button in the TFT to do a digital output on the mega.

Can someone send me the sample code for the TFT and the mega to send and read the serial bit

Conversely the return a serial bit from the mega to change the indication on the TFT from off to on

Thanks in advance. Ben.