Re-write URL (plugin : rewrite)

Hello wordpress’s world,

I’am using a “booking template” . from the link : “www.mysite.com/catalog” I can get the list of booking services.

Is it possible to change “/catalog” to another name “/NameOfMyService”?

In fact, “/catalog” is not post or page … it’s php script executing from them files.

I tried to use the plugin named “Rewrite” … but i don’t have no idea how to add rewriting rules.

Can u help me plz,
thank’s a lot !