lcd.init(); error

i attach the code

and this is the error with ( lcd.init(); ) line

Arduino: 1.8.7 (Mac OS X), Board: “Arduino Nano, ATmega328P (Old Bootloader)”

In file included from /Users/khalilaltaweel/Downloads/RFID_door_lock_code 3/RFID_door_lock_code/RFID_door_lock_code.ino:13:0:
/Users//Documents/Arduino/libraries/Newliquidcrystal_1.3.5/LiquidCrystal_I2C.h: In function ‘void setup()’:
/Users//Documents/Arduino/libraries/Newliquidcrystal_1.3.5/LiquidCrystal_I2C.h:154:9: error: ‘int LiquidCrystal_I2C::init()’ is private
int init();
RFID_door_lock_code:46:12: error: within this context
Multiple libraries were found for “LiquidCrystal_I2C.h”

RFID_door_lock_code.ino (22.4 KB)

What are you trying to achieve by calling lcd.init() ?
Have you seen it in any of the LCD examples ?
Why is there no lcd.begin() in your code ?

There are several different LCD libraries called LiquidCrystal. They don't all use the same commands. You need to make sure that the library that a sketch uses is the one that you have installed.