проблем със страница във форума

[Maistorcheto]

значи искам да си добавя страница към форума но имам проблем урока е от тук

на страницата ми дава следните грешки

[phpBB Debug] PHP Notice: in file /includes/session.php on line 990: Cannot modify header information - headers already sent by (output started at /portal.php:1)
[phpBB Debug] PHP Notice: in file /includes/session.php on line 990: Cannot modify header information - headers already sent by (output started at /portal.php:1)
[phpBB Debug] PHP Notice: in file /includes/session.php on line 990: Cannot modify header information - headers already sent by (output started at /portal.php:1)
[phpBB Debug] PHP Notice: in file /includes/functions.php on line 3760: Cannot modify header information - headers already sent by (output started at /portal.php:1)
[phpBB Debug] PHP Notice: in file /includes/functions.php on line 3762: Cannot modify header information - headers already sent by (output started at /portal.php:1)
[phpBB Debug] PHP Notice: in file /includes/functions.php on line 3763: Cannot modify header information - headers already sent by (output started at /portal.php:1)
[phpBB Debug] PHP Notice: in file /includes/functions.php on line 3764: Cannot modify header information - headers already sent by (output started at /portal.php:1)