How To Make Green Selection Box To Move Around

I'm making a simple game where there's a 10x10 grid and you can move around a selection box and you can move around. I've been trying to make the green selection box to move around but it won't move! I only have right movement in the code but it won't work so far. Here are the classes that have to do greatly with each other.

import java.awt.Canvas;
import java.awt.Color;
import java.awt.Graphics;
import java.awt.event.KeyEvent;
import java.awt.image.BufferStrategy;
import java.util.Random;
 
public class Game extends Canvas implements Runnable{
private static final long serialVersionUID = 1L;
 
[Code] ....

I also tried an approach where you click with the move and it snaps to a tile grid but that didn't work either.