How to insert data into radgrid

protected void RadGrid_Details_InsertCommand(object sender, GridCommandEventArgs e)
{

           GridDataItem dataItem = e.Item as GridDataItem;
            
            ID = int.TryParse(dataItem["ID"].Text);
            string FirstName = dataItem["FirstName"].Text;
            string LastName = dataItem["LastName"].Text;
           
          
}