How to do dynamic scrolling on any webpage

import io.github.bonigarcia.wdm.WebDriverManager;
import org.openqa.selenium.*;
import org.testng.annotations.Test;

public class ScrollDownTestAnkurDemo {

    @Test
    public static void  getDynamicScrollDownByAnkur()  {

        WebDriver driver = WebDriverManager.chromedriver().create();
        driver.manage().window().maximize();
        driver.get("https://www.google.com");
        driver.findElement(By.name("q")).sendKeys("Facebook"+ Keys.ENTER);

        JavascriptExecutor js = (JavascriptExecutor) driver;

        //Get the actual whole WebPage Height
        Object height = js.executeScript("return document.body.scrollHeight");
        String ht = height.toString();
        System.out.println("Page height is : "+ht);

        //Calculating the Number of Steps to scroll using 450 Pixel in each scroll
        float htInt = Integer. parseInt(ht);
        System.out.println(" The number of steps to scroll down with each 450 px  :"+Math.round(htInt/450));
        int y = 0;
        int z = 450;
        for(int i = 0 ; i < Math.round(htInt/450)-1 ; i ++){
                js.executeScript("window.scrollBy(" + y + "," + z + ")","");
                y=z;
                z=z+450;
            System.out.println(" After Execution the scroll height y :"+y +" z is :"+z);
        }
        driver.quit();
    }
}