Use composer to install PhpSpreadsheet into your project:
composer require phpoffice/phpspreadsheet
Or also download the exe file from the link.
https://phpspreadsheet.readthedocs.io/en/latest/#installationHello World Example
This would be the simplest way to write a spreadsheet:
<?php
require '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');