No code works for I2C LCD module

I am running SDA and SCL on pins 20 and 21 on my mega 2560. Unfortunately, this code isn’t working, what am I doing wrong???

#include <Wire.h>
#include <FastIO.h>
#include <I2CIO.h>
#include <LCD.h>
#include <LiquidCrystal.h>
#include <LiquidCrystal_I2C.h>

#define GPIO_ADDR 0x27
LiquidCrystal_I2C lcd(0x27, 2, 1, 0, 4, 5, 6, 7, 3, POSITIVE); // set the LCD I2C address

void setup() {

lcd.begin(16,2);

}

I get this error message
Arduino: 1.8.5 (Windows 10), Board: “Arduino/Genuino Mega or Mega 2560, ATmega2560 (Mega 2560)”

C:\Users\JACOB.no\AppData\Local\Temp\ccswVYFk.ltrans0.ltrans.o: In function `main’:

ccswVYFk.ltrans0.o:(.text.startup+0x15c): undefined reference to `loop’

collect2.exe: error: ld returned 1 exit status

Multiple libraries were found for “FastIO.h”
Used: C:\Users\JACOB.no\Documents\Arduino\libraries\Newliquidcrystal_1.3.5
Not used: C:\Program Files (x86)\Arduino\libraries\Newliquidcrystal_1.3.5
Not used: C:\Program Files (x86)\Arduino\libraries\Newliquidcrystal_1.3.5
Not used: C:\Program Files (x86)\Arduino\libraries\Newliquidcrystal_1.3.5
Not used: C:\Program Files (x86)\Arduino\libraries\Newliquidcrystal_1.3.5
exit status 1
Error compiling for board Arduino/Genuino Mega or Mega 2560.

This report would have more information with
“Show verbose output during compilation”
option enabled in File → Preferences.

You have to define a loop function, even if it is empty.

@mitorbust, do not cross-post. Do not hijack. Other post removed.