help with php pdo mysql

What I want to do is run a query based on user input (fname, lname passed from an html program). If I don't find a record, I want to close the database and run a different htm file
Thanks for any help.

This is a piece of my code:

PHP Code:

---

<?php
$fname = filter_input(INPUT_POST, "fname");
$lname = filter_input(INPUT_POST, "lname");

try    
    {
    $connect = new PDO('mysql:host=localhost;dbname=xxxxxx', "xxxxxx", "xxxxxx");
    echo 'Connected to database<br />';
    $connect->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION);

    $sql = "SELECT * FROM contacts WHERE firstname = '$fname' && lastname = '$lname' ";


    $connect = null;        
    }
             
catch(PDOException $e)
     {
     echo 'ERROR: ' . $e->getMessage();
     }
?>

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