Hi Gianni,
Oops, I thought I had linked the tutorial on the reply above, should be there now!
The methods that are being used to serve the webpage are perfect for one device - providing up to date information for one client is easy but two at the same time is a bit harder. The easiest get out of jail free card would be to grab another ESP32 to host a seperate server for another device. David has an awesome guide on getting a cheaper ESP32 working on this topic: FireBeetle ESP32-E IoT Microcontroller with header (Supports Wi-Fi & Bluetooth) (DFR0654-F)
As for making the buttons momentary, the webpage is constructed using pure HTML(and a little bit of CSS to clean up the formatting). While simple it doesnt allow for a momentary property to be set, more about buttons here:HTML button tag
NodeMCU might have some functionality where you can setup a momentary button though.
