Simple Code

#include <Arduino.h>

int solenoidValvePin = 27; // Solenoid Valve's pin. GPIO26 on NodeMCU ESP32
int powerLED = 25;         // LED that goes on when the ESP32 is energized. GPIO25 on NodeMCU ESP32

int count = 0;
void setup()
{
  Serial.begin(115200);
  pinMode(solenoidValvePin, OUTPUT);
  pinMode(powerLED, OUTPUT);
  digitalWrite(powerLED, HIGH);
  delay(6000); // Library recommendations to start the WiFi hardware from the ESP32
}

void loop()
{
  Serial.println(count);
  digitalWrite(solenoidValvePin, HIGH);
  delay(2000);
  digitalWrite(solenoidValvePin, LOW);
  delay(2000);
  count++;
}