To or Cc multiple wordpress contacts via filtered db query

i want to send email to multiple contacts via db query. i was trying to do so using Contact Form 7. i’d like to save myself hours of trial and error coding. okay 2 things at issue: 1.) the Contact Form 7 validation won’t allow multiple email address. 2.) i don’t need multiple “From:” headers. i need multiple “To:”, or “Cc:”. That’s my fault for being stupid.

<?php if (current_user_can('edit_users')) { 
        $email_array = array();
        $email_concat = '';
        $userlogin_array = array();
        $userlogin_concat = '';
        foreach ($bulk_user_ids as $user_id) {
            $user = get_user_by('id', $user_id); 
            $email_concat .= $user->user_email .','; 
            $userlogin_concat .= $user->user_login .', ';
        }         
?> 
<form action="users.php" method="post" class="wpcf7-form init" aria-label="Contact form" novalidate="novalidate" data-status="init">
<input size="40" class="wpcf7-form-control wpcf7-text wpcf7-validates-as-required" autocomplete="name" aria-required="true" aria-invalid="false" value="<?php 
echo $userlogin_concat; 
?>" type="text" name="your-name">
</p>
<p><label>Your email<br>
<input size="40" class="wpcf7-form-control wpcf7-text wpcf7-email " value="<?php 
echo $email_concat; 
?>" type="email" name="your-email"> 

I was expecting to learn what happens when this code is executed. It results in error. I suppose it’s javascript validation. Then I realize I’m using the wrong field anyway. Before I start over, I’d like to know if anyone has a recommended solution.

I was advised to place some code in a functions.php file, but that seems like bad advice. What if change themes?