C#

Good evening; I'm looking for a source code to make a datagridView with Multi Header Columns and Multi Cell Header As shown

All that is in gray is the head that I am trying to code

private TextBox txtBox1 = new TextBox();
private ComboBox cmbx1 = new ComboBox();
private TextBox txtBox2 = new TextBox();
private TextBox txtBox3 = new TextBox();
private Button btn1 = new Button();
int configLineIndex = 1;
private void btnCuRepairConfigAddLine_Click(object sender, EventArgs e)
{
    configLineIndex++;
    tbxHorizontalIndex = 21;

    txtBox1 = new TextBox();
    txtBox1.Name = "line" + configLineIndex + "a";
    int tbxWidth = 285;
    this.txtBox1.Location = new System.Drawing.Point(tbxHorizontalIndex, tbxVerticalIndex + 30);
    this.txtBox1.Size = new System.Drawing.Size(tbxWidth, 20);
    this.Controls.Add(txtBox1);

    cmbx1 = new ComboBox();
    cmbx1.Name = "line" + configLineIndex + "b";
    this.cmbx1.Location = new Point(tbxHorizontalIndex + 299, tbxVerticalIndex + 30);
    this.cmbx1.Size = new Size(121, 21);
    this.cmbx1.Items.Add("addAfter");
    this.cmbx1.Items.Add("addBefore");
    this.cmbx1.Items.Add("Replace");
    this.Controls.Add(cmbx1);

    txtBox2 = new TextBox();
    txtBox2.Name = "line" + configLineIndex + "c";
    tbxWidth = 320;
    this.txtBox2.Location = new System.Drawing.Point(tbxHorizontalIndex + 435, tbxVerticalIndex + 30);
    this.txtBox2.Size = new System.Drawing.Size(tbxWidth, 20);
    this.Controls.Add(txtBox2);

    txtBox3 = new TextBox();
    txtBox3.Name = "line" + configLineIndex + "d";
    tbxWidth = 320;
    this.txtBox3.Location = new System.Drawing.Point(tbxHorizontalIndex + 770, tbxVerticalIndex + 30);
    this.txtBox3.Size = new System.Drawing.Size(tbxWidth, 20);
    this.Controls.Add(txtBox3);

    btn1 = new Button();
    btn1.Name = "line" + configLineIndex + "e";
    this.btn1.Location = new Point(tbxHorizontalIndex + 1110, tbxVerticalIndex + 30);
    this.btn1.Size = new Size(20, 20);
    this.btn1.Text = "X";
    this.Controls.Add(btn1);


    //tbxHorizontalIndex = tbxHorizontalIndex + tbxWidth + 10;
    tbxVerticalIndex = tbxVerticalIndex + 30;
}

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