now go to your reseller panel and then go to cpanel adevert settings and add following lines and replace yourdomain.com/template with your company domain
<link rel="stylesheet" type="text/css" href="https://yourdomain.com/template/cpanel/styles.css">
<link rel="stylesheet" type="text/css" href="https://yourdomain.com/template/cpanel/styles.min.css">
<link rel="stylesheet" type="text/css" href="https://yourdomain.com/template/cpanel/icon_spritemap.css">
Now go to customization and edit .htaccess and add following lines and replace yourdomain.com/template with your company domain
ErrorDocument 400 https://yourdomain.com/400.html
ErrorDocument 401 https://yourdomain.com/401.html
ErrorDocument 403 https://yourdomain.com/403.html
ErrorDocument 404 https://yourdomain.com/404.html
ErrorDocument 503 https://yourdomain.com/503.html
Now go to customization and Default Index Page and add following lines
<html>
<head>
<title>Default Index Page</title>
</head>
<body>
<h2 style="text-align:center">Congratulations</h2>
<p style="text-align:center">Your account have been created successfully please change your website files using file manager or ftp</p>
</body>
</html>
Now go to Package and create a package for your domain name and add the details and save settings now everything is done rest assure