To confirm whether or not your email message was sent out from your SMTP server, you can do something like this.  Getting email read notification option is done by adding a custom header called "Disposition-Notification-To" to the mail message:

protected void btnSendEmail_Click(object sender, EventArgs e)
{

    MailMessage msg = new MailMessage();
    SmtpClient client = new SmtpClient();

   //Add a custom header called Disposition-Notification-To to the mail message:

    msg.Headers.Add("Disposition-Notification-To", "email address");

   
    try

   {
        client.Send(msg);
        Response.Write("Your mail was sent.");
    }

    catch (SmtpException ex)

   {
        Response.Write(ex.Message);
    }

}