Как в данном коде поменять картинку на свою - C#

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Windows.Forms;
 
namespace pacman
{
    public partial class Form1 : Form
    {
        Graphics _gr;
        BufferedGraphics _bufferedGraphics;
        BufferedGraphicsContext _bufferedGraphicsContext;
 
        Rectangle _rect = new Rectangle(180, 180, 10, 10);
        Pen _pen = new Pen(Color.Green, 10);
 
        public Form1()
        {
            InitializeComponent();
            StartPosition = FormStartPosition.CenterScreen;
 
            KeyDown += new KeyEventHandler(Form1_KeyDown);
            Paint += new PaintEventHandler(Form1_Paint);
            SizeChanged += new EventHandler(Form1_SizeChanged);
 
            _bufferedGraphicsContext = BufferedGraphicsManager.Current;
            InitializeGraphics();
        }
 
        void Form1_SizeChanged(object sender, EventArgs e)
        {
            InitializeGraphics();
        }
 
        void Form1_KeyDown(object sender, KeyEventArgs e)
        {
            if (e.KeyCode == Keys.Left)
                _rect.Location = new Point(_rect.Left - 5, _rect.Top);
            if (e.KeyCode == Keys.Right)
                _rect.Location = new Point(_rect.Left + 5, _rect.Top);
            if (e.KeyCode == Keys.Up)
                _rect.Location = new Point(_rect.Left, _rect.Top - 5);
            if (e.KeyCode == Keys.Down)
                _rect.Location = new Point(_rect.Left, _rect.Top + 5);
            Refresh();
        }
 
        void Form1_Paint(object sender, PaintEventArgs e)
        {
            DrawToBuffer();
        }
 
        private void DrawToBuffer()
        {
            _bufferedGraphics.Graphics.Clear(BackColor);
            _bufferedGraphics.Graphics.DrawEllipse(_pen, _rect);
            _bufferedGraphics.Render();
        }
 
        private void InitializeGraphics()
        {
            _gr = CreateGraphics();
            _bufferedGraphics = _bufferedGraphicsContext.Allocate(_gr, ClientRectangle);
        }
    }
}