String command;
#include <LiquidCrystal_I2C.h>
LiquidCrystal_I2C lcd(0x27,16,2);

void setup() {
  Serial.begin(9600);
  lcd.backlight();
  lcd.init();

  delay(2000);

  Serial.println("Ai Chat assistant is on!");
}

void loop() {
  if (Serial.available()) {
    command = Serial.readStringUntil('\n');
    command.trim();
    if (command.equals("I need help"))
    {
      lcd.clear();
      lcd.setCursor(0,0);
      lcd.println("Sure what is it?");
    }
    if (command.equals("What is 1+1"))
    {
      lcd.clear();
      lcd.setCursor(5,0);
      lcd.println(1+1);
    }
    if (command.equals("Thanks") || command.equals("Thx") || command.equals("Thank you"))
    {
      lcd.clear();
      lcd.setCursor(0,0);
      lcd.println("No problem.");
    }
  }
}