Hi Chaitanya, I have show 2 examples here. Pick which is best for you
List<Image> imageLst = new List<Image>();
imageLst.Add(image);
Random random = new Random();
pictureBox1.Image = imageLst[random.Next(0, images.Count - 1)];
List<String> imagePathList = new List<String>();
imagePathList.Add(imagePath);
Random random = new Random();
pictureBox1.ImageLocation = imagePathList[random.Next(0, images.Count - 1)];