Put serial input string on an LCD screen

This is my current program:

#include <LiquidCrystal.h>
LiquidCrystal lcd(8, 9, 4, 5, 6, 7);
char prevValue;

void setup() {
    lcd.begin(16, 2);

void loop() {
  if (Serial.available() > 0) {
    char value = Serial.read();
    if (prevValue != value){
      prevValue = value;

When you type in any char in the serial monitor, it will print it on my LCD screen.
Now I want to make it read an entire string. Also, the part of my program that listens for a new char to change the screen will not work if the inputted char is the same as the previous one. Any suggestions/help?

What line ending, if any, do you have selected in the serial monitor ?

Do you want the user to type a string, press Return and for the string to appear on the LCD or is each character entered individually followed by Return ?