Regardless of the details, you need to put the implemention into a
separate file so you can say:
<?php
include('hdr.php'); // includes functions header(), footer(),
// and anything else needed by most pages
header('Title', etc...);
// page content goes here
footer();
?>
One easy way to do this is to make a table to contain it all.
header() then contains:
<table>
<tr>
<td>top bar stuff</td>
</tr>
<tr>
<td width=???>Left side menu</td>
<td width=???>
and footer() closes it up:
</td>
</tr>
</table>