how to delete a specific row from Gridview using builtin delete command button of gridview

DataTable dt1 = new DataTable();

        protected void Page_Load(object sender, EventArgs e)
        {
            if (!Page.IsPostBack)
            {
                gridVIEWData();
                GridView1.DataSource = dt1;
                GridView1.DataBind();
            }
    private void gridVIEWData()
        {
            
            dt1.Columns.Add("pName", typeof(string));
            dt1.Columns.Add("pCategory", typeof(string));
            dt1.Columns.Add("price", typeof(string));
            dt1.Columns.Add("pQuantity", typeof(string));
            dt1.Columns.Add("totalPrice", typeof(string));
            Session["dtInSession"] = dt1;   //Saving Datatable To Session
        }
    protected void Button3_Click(object sender, EventArgs e)
        {
            if (Session["dtInSession"] != null)
                dt1 = (DataTable)Session["dtInSession"]; //Getting datatable from session 

            
                Int32 total = Convert.ToInt32(txt_quantity.Text) * Convert.ToInt32(txt_price.Text);
                DataRow dr = dt1.NewRow();
                dr["pName"] = DropDownList2.SelectedItem;
                dr["pCategory"] = DropDownList1.SelectedItem;
                dr["price"] = txt_price.Text;
                dr["pQuantity"] = txt_quantity.Text;
                dr["totalPrice"] = total;
                dt1.Rows.Add(dr);

                
                Session["dtInSession"] = dt1;     //Saving Datatable To Session 

                GridView1.DataSource = dt1;
                GridView1.DataBind();
            
            }
    protected void GridView1_RowDeleting(object sender, GridViewDeleteEventArgs e)
        {
            
           // string value = GridView1.DataKeys[e.RowIndex].Values["price"].ToString();
            //GridView1.DeleteRow(Convert.ToInt32(value));
            //GridView1.DeleteRow(GridView1.SelectedIndex);
            
               // dt1.Rows.RemoveAt(GridView1.SelectedIndex);
            Int32 index = GridView1.SelectedIndex;
            GridView1.DeleteRow(index);
        }