int satir, sutun, minute, tik;
    List<Button> buttonList = new List<Button>();
    Random rnd = new Random();

    private void timerRandom_Tick(object sender, EventArgs e)
    {
        int rndNumber = rnd.Next(0, satir*sutun);

        // buttonList[rndNumber].Name ??? Back.Color = Color.Red;
        //  should change the color of the buttons I created below
    }

    int i = 0, j = 0;
    private void btnStart_Click(object sender, EventArgs e)
    {
        panel.Controls.Clear();

        switch (comboBoxLevel.Text)
        {
            case "1.Seviye":
                satir = 5; sutun = 5; minute = 60000; tik = 5000;
                break;
            case "2.Seviye":
                satir = 7; sutun = 7; minute = 120000; tik = 5000;
                break;
            case "3.Seviye":
                satir = 9; sutun = 9; minute = 1800000; tik = 500;
                break;
            default:
                break;
        }

        for (i = 0; i < satir; i++)
        {
            for (j = 0; j < sutun; j++)
            {
                Button btn = new Button();
                btn.Name = "btn" + i + j;
               // btn.Text = "Button" + i + " , " + j;
                btn.Size = new Size(80, 60);
                btn.Location = new Point(i * 80, j * 60);
                btn.Click += buttonClick;
                panel.Controls.Add(btn);
                buttonList.Add(btn);
            }
        }
        timerRandom.Interval = tik;
        timerRandom.Start();


    }