I need help with my code

<?=
include('config/config.php');

class Login {
$username=$_POST['UserName'];
$password=$_POST['PassPhrase1'];
}

class Register extends Login {
$login =

// $username + $password

function LogMeIn($dualipa, $dualipa2) {
$login .=

}
}
?>
<!DOCTYPE HTML/>
<HTML/>
<HEAD/>
<TITLE/>Registrera konto!</TITLE>
<STYLE/>
input[type=text], input[type=password] {
padding: 12px;
}
.button {}
</STYLE>
</HEAD>
<BODY>
<FORM METHOD="POST"/>
Användarnamn:<br>
<INPUT TYPE="text" NAME="UserName" REQUIRED/><br>
Lösenord:<br>
<INPUT TYPE="password" NAME="PassPhrase1" REQUIRED/><br><br>
<BUTTON TYPE="submit"  NAME="submit" CLASS="button" ROLE="x" SYNPUNKT="2" CROSSORIGIN="anonymous"/>Registrera konto</BUTTON>
</FORM>
</BODY>
</HTML>

It should be basic auth