How to redirect on particular page in wordpress? [closed]

You should get ID of the page you’re looking for:

$page = get_page_by_title('thank-you');
wp_redirect(get_permalink($page->ID));
exit;

It looks like you want to get page by slug. If that’s the case, you should use this function instead.

Also, for Location header don’t use space after “Location” string:

header("Location: http://localhost/mysite/faq");