you have to enable that in the php.ini file
in my version, it was in this location...yours may vary
c/xampp/php/php.ini
look for this line ( mine was around line 952)
;extension=php_curl.dll
remove the ; so it looks like this
extension=php_curl.dll
save it, and it should work for you
if you had xampp running...you will need to exit it and restart it for the changes to take effect