Check with your hardware interface connection between arduiono and LCD and refer the below code how the LCD code functions
https://www.engineersgarage.com/embedded/arduino/how-to-interface-4-bit-lcd-with-arduino
Check with your hardware interface connection between arduiono and LCD and refer the below code how the LCD code functions
https://www.engineersgarage.com/embedded/arduino/how-to-interface-4-bit-lcd-with-arduino