This is a common request.
At first, it seems that the best way to use PHP is to allow moderators/administrators to the site to go in and make changes to certain things without messing up the style/display but the actual site is HTML. You can certainly do this.
Just look into the file reading and writing commands.
I think the heredoc syntax will be perfect for this if you choose to go that route. You need to set all your variables like $nameofsite and $newsarticle1 before the heredoc.
$htmlbuff=<<<QQQ
<html>
<title><head>{$nameofsite}</head></title>
<body bgcolor=FFFFFF text=000000 link=FFFF00>
<h1>Welcome to so-and-so.</h1>
The news for the day is:
{$newsarticle1}
{$newsarticle2}
{$newsarticle3}
</body>
</html>
QQQ;
echo $htmlbuff;
But, I would reconsider having the entire site PHP.