So I have a regular PHP page which includes the header, body, and the footer.
So
<?php include('header.html');
?>
So header.html has <html>... content </html>
Same with Footer.html
and the index.php has one <html>Tag too.</html>
So is this bad for SEO or something else?
How to fix it?
Thanks.
Search engines will see exactly what the browser sees. So they know as much about your includes as the user: Nothing.
However, according your question your HTML code is horribly invalid as it seems to look like that:
Your templates should be like that:
header:
content:
footer: