Button 3 wires G V S

Other Hardware General Electronics
6

Ignore the V connection. Looking at the pictures it's not connected to anything at all. My guess is they have one PCB for multiple uses. So ignore V.

Just use G and S. It doesn't matter which is which, it's just a switch. Then use it exactly like any other pushbutton.

Simplest way: connect it between input pin and ground, and enable INPUT_PULLUP on the pin

void setup() {
  pinMode(2, INPUT_PULLUP);
  pinMode(13, OUTPUT);
}

void loop() {
  digitalWrite(13, !digitalRead(2));
}