Use PHP inside HTML.

PHP generates HTML and not the other way around.

As a quick solution I would rename the .html files to .php and use the existing html with the php heredoc function, ex:

<?php

echo <<< EOF

your html code here

EOF;

?>

if you need to connect to a database, you can append the db output to the existing html, like this:

<?php

$db = new mysqli('localhost', 'user', 'pass', 'demo');

if($db->connect_errno > 0){
    die('Unable to connect to database [' . $db->connect_error . ']');
}
    
echo <<< EOF
first part of the html here
EOF;

//Queries the DB and outputs the results of all **employees**
$result = $db->query("SELECT id, name, salary FROM employees");
while (list($id, $name, $salary) = $result->fetch(PDO::FETCH_NUM)) {
echo <<< EOF
 <tr>
          <td><a href="info.php?id=$id">$name</a></td>
          <td>$salary</td>
          </tr>
EOF;
}

echo <<< EOF
second part of the html here
EOF;

//and so on...


?>

Make sure you run the code on a server that supports php.

• HEREDOC (EOF) function