I have not run into the problem with XAMPP that you are talking about and have installed many a time without any need for entering a mobile phone number.
are you downloading from apache friends?
that is the official XAMPP site.
for the cURL issue, create a new blank PHP file with the following code in it:
<?php phpinfo(); ?>
this will show information about the PHP Server, one of the settings it will show is the location for the loaded php.ini file.
make note of the loaded php.ini file location, and enable the cURL dll in that file.
if you continue to have a problem, make note of the extensions directory, and make sure the cURL dll is in that directory.