General developer forum

Here is how you can create a spreadsheet

You need to find the excact path of the autoload.php file.
Here is my code below.

require_once('../../config.php');
require_once($CFG->libdir . '/phpspreadsheet/vendor/autoload.php');

use PhpOffice\PhpSpreadsheet\Spreadsheet;
use PhpOffice\PhpSpreadsheet\Writer\Xlsx;

$spreadsheet = new Spreadsheet();
$sheet = $spreadsheet->getActiveSheet();

$sheet->setCellValue('A1', 'Hello World !');
$writer = new Xlsx($spreadsheet);
$writer->save('hello world.xlsx');