I'm new to all this and basically what I'm trying to do is get my website to execute this code:

<?php
session_start(); $toplinks = "";
if (isset($_SESSION['id'])) {
$userid = $_SESSION['id'];
$username = $_SESSION['username'];
$toplinks = '<a href="member_profile.php?id=' . $userid . '">' . $username . '</a> &bull;
<a href="member_account.php">Account</a> &bull;
<a href="logout.php">Log Out</a>';
} else {
$toplinks = '<a href="join_form.php">Register</a> &bull; <a href="login.php">Login</a>';
}
?>

within a .html webpage how would i do that? can I convert what this is doing to html ? what do you suggest and if it is converting it could you please show me how or just do it thanks.

See http://php.net/manual/en/function.echo.php

(I can't see that the PHP manual entry for echo is particularly useful...)

You need more program than this, and a database-backed server to store the information. Where did this fragment come from?

No, you cannot "convert" this to html.