Change allowed upload file types

in LocalSettings.php

$wgFileExtensions = array_merge(
    $wgFileExtensions, array(
        'pdf', 'ppt', 'jp2', 'webp', 'doc','docx', 'xls', 'xlsx', 'jar', 'exe', 'txt', 'json', 'xml', 'zip'
        )

for file size

  $wgMaxUploadSize = 2000000000;