please i need help on php and server

HELLO ALL

i want to READ RSS form my site and i found a code on that site http://www.w3schools.com/php/php_ajax_rss_reader.asp

i used this code by copy and past it on my site http://sa7afa.net/1.html

but when i compile that code on the server i found some errors which i can't solve it and i want to know what i should do

some peaple said that my server should provide XML and some said that the problem is that my server can't access external links

i want to know what i should do in details and what is the problem and if the problem is on the server i want to know what i should do on the server configuration

the code which i used on http://www.w3schools.com/php/php_ajax_rss_reader.asp

the page which i used the code on it http://sa7afa.net/1.html

my mail is haa912005@yahoo.com

THANKS