PHP: add a download as csv file button in report page

Suppose  we have  a form to post data from MySQL to report.php
<form name="form1" action="report.php" method="POST">
Now we not only want to display data in the table in report.php, we also need ot add a button to download as CSV file.
In report.php below, we have a table to display data. We also  have a hidden input to transfer data
to new action script report_csvA.php to download as csv file.
     <form name="getcvs" action="report_csvA.php" method="POST">
         <input type="submit" name="submit" value="Download CSV file" class="input-button" />
    
      <p>
   <table   cellspacing="0" border="1" style="font-size:10" width="100%">
   <thead>
   <tr>
      <!-- <th scope="col"><a href="#program_name" onclick="setSort('program_name')">Member Name</a></th> -->
      <!-- <th scope="col"><a href="#last_name" onclick="setSort('contact_last_name')">Society</a></th> -->
      <th scope="col" width=35% style="text-align:left" >Type of Activity </th>
      <th scope="col"  style="text-align:left" >Number of Activity</th>
      <th scope="col" style="text-align:left">Hours of Instruction</th>
      </tr>
   </thead>
 <tr>
<?php
        $count_basic_skills = $_POST['count1'];
        $count_hours_bs = $_POST['count2'];
         echo('<tr>');
         echo '<td>Basic Skills</td>';
         echo '<td>'.$count_basic_skills.'</td>';
         echo '<td>'.$count_hours_bs.'</td>';     
         echo('</tr>');
?>
  </table>
      <input type="hidden" name="count_basic_skills" value="<?php echo $count_basic_skills;?>">
      <input type="hidden" name="count_hours_bs" value="<?php echo $count_hours_bs;?>">
        </form>


In  report_csvA.php, a csv file is produced for download:
<?php
header('Content-Type: application/x-excel');
header('Content-Disposition: attachment; filename="cesei_activity_log.csv"');
header('Expires: 0');
header('Cache-Control: must-revalidate, post-check=0, pre-check=0');
header('Pragma: public');
$headers=array('Type of Activity','Number of Activity','Hours of Instruction');
 $row_1=array('Basic Skills', $_POST['count_basic_skills'],$_POST['count_hours_bs']);
echo(implode(',',$headers));
echo("\n");
echo(implode(',',$row_1));
echo("\n");
?>

Video: PHP: add a download as csv file button  in report page