The requirements are rather too complex to go into here, but if you Google for the requirements, you should find the details fairly easily. Pages does have screenplay and storyboard templates, which may suit your needs, but it still tends to require a rather linear approach to writing your screenplay, which is rather limiting.
I'd strongly recommend using an application designed for the purpose. Final Draft is the industry standard and very powerful, but rather expensive, as is Montage. A good cheap alternative is Scrivener, which has formatting templates for both stage and screen writing, and allows you access to your screenplay, storyboard and research in a single interface.