Addition of numbers using button won't work

Projects Programming
7

gfvalvo:
Always re-post the complete code after making changes.

Sorry

Here the one with "static":

// constants won't change. They're used here to set pin numbers:
const int buttonPin = 2;     // the number of the pushbutton pin
#include <LiquidCrystal_I2C.h>
LiquidCrystal_I2C lcd(0x3F, 2, 1, 0, 4, 5, 6, 7, 3, POSITIVE); 
// variables will change:
int buttonState = 0;         // variable for reading the pushbutton status

void setup() {
  // initialize the pushbutton pin as an input:
  pinMode(buttonPin, INPUT);
  
  lcd.begin(16,2);
}

void loop() {
  
  // read the state of the pushbutton value:
  buttonState = digitalRead(buttonPin);
int stock = 20;
  static number = 1;
  
  // check if the pushbutton is pressed. If it is, the buttonState is HIGH:
  if (buttonState == HIGH) {
   int plus = stock +number;
     lcd.setCursor(0, 0);
  lcd.print("Number: ");
  lcd.print(plus);
  } 
}

And the one with global

// constants won't change. They're used here to set pin numbers:
const int buttonPin = 2;     // the number of the pushbutton pin
#include <LiquidCrystal_I2C.h>
LiquidCrystal_I2C lcd(0x3F, 2, 1, 0, 4, 5, 6, 7, 3, POSITIVE); 
// variables will change:
int buttonState = 0;         // variable for reading the pushbutton status
number = 1;
void setup() {
  // initialize the pushbutton pin as an input:
  pinMode(buttonPin, INPUT);
  
  lcd.begin(16,2);
}

void loop() {
  
  // read the state of the pushbutton value:
  buttonState = digitalRead(buttonPin);
int stock = 20;
  
  
  // check if the pushbutton is pressed. If it is, the buttonState is HIGH:
  if (buttonState == HIGH) {
   int plus = stock +number;
     lcd.setCursor(0, 0);
  lcd.print("Number: ");
  lcd.print(plus);
  } 
}