Trobleshoot post and get

<?php
 //Start a session
  session_start();
  //unset and reset any existing session
  session_unset();
  ?>
<!DOCTYPE html>
<html>
<head>
<script type="text/javascript">
function delayedRedirect()
{
window.location = "url to page you want to go after login"
}
</script>
</head>
<body onLoad="setTimeout('delayedRedirect()', 8000)" style="background-color:#fff;">

<?php
//this is a link to my connection string. you can type it here as well
include 'tconslocal.php';
//eg:  $con = mysqli_connect('server','username','password','database') or die('Unable To connect');

//assign variable here either through post or get

//for post use this
$username=mysqli_real_escape_string($con,$_POST['username']);
 $password=mysqli_real_escape_string($con,$_POST['password']);

//for GET use this
 $username=mysqli_real_escape_string($con,$_GET['username']);
 $password=mysqli_real_escape_string($con,$_GET['password']);

echo "this is username: ".$username;
echo "|| This is password: ".$password;

//$mysql_query="SELECT * FROM tablename where username= '$username' AND password= '$password'";
//$result = mysqli_query($con,$mysql_query);
//$count= mysqli_num_rows($result);
// If result matched username and password, table row must be 1 row
//if($count>0)
//{
//use this if you will be using the table information in the row returned
//while($row = $result->fetch_assoc())
//{
//here iam assigning the id from the table row into a session variable so i can use it later
//$_SESSION['SESS_userID'] = $row['userid'];
//close the session write process when done
//session_write_close();
//}
//echo "User Has Been Logged In Successfully. You will be redirected to the dashbooard in 5 seconds";
//exit;
//}
//else
//{
//echo "User Not Found. You will be redirected to the dashbooard in 5 seconds";
//exit;
//}
?>
</body>
</html>