SO is for asking specific questions related to programming. Even though your question is related to programming you are not asking a specific question.
A quick google search for "PHP read RSS feeds gives you a list of very good links which can get you started.
How to Read an RSS Feed With PHP – screencast
Try out the example and see if it fits your requirement. If you have any specific questions then come back to SO and I am sure everyone will be glad to help.
