how to visit another webpage in php

How can all the users in my table visit a particular url at a click in php

    $sql2 = "SELECT * FROM `members_profilee` WHERE `RegNumber` = '$RegNumber'";
            $res2 =  mysqli_query($conn,$sql2);
            while ($row = mysqli_fetch_array($res2,MYSQLI_ASSOC)) {
                $phone = $row['Phone'];
                $lastName = $row['LastName'];
                $firstName = $row['FirstName'];

            }

         $url = 'http://api.smartsmssolutions.com';


         <div class="form_box_new" align="left">
                <?php if (isset($error)) echo $error; ?>
                <?php if (isset($message)) {echo $message; 
                echo "<script type='text/javascript'>window.location.href = '$url';</script>";