@php for native php with laravel

Been working on a group project and it's been a while me using just laravel for developing php, one of my teammates sent me his work as plain php file with multiple <?php ?> tags inside it even the connection using PDO and other stuff been trying to merge these his files to mine for a while trying not to reform his files so I don't commit any changes to what he knows he have typed but I couldn't help it its too much errors
I've tried to replace each php tag with a @php and @endphp with changes to database connections and stuff but nothing seem to be working fine
Any help please with this!!