In addition to the correct answer by Dave:
You could load the whole thing and then select and cut out unwanted part of it. However, the notion of page is not defined. Pages are created on the fly when you print the document. They are not really part of document. To best of my knowledge, even a forced page break is not defined in the RTF format. Your criteria of the selection of the document part simply makes no certain well-defined sense. You can select some part of document according to its structure: a paragraph, a set of paragraphs under certain title or something like that.
Generally, RTF format provides too poor means of defining document structure. I would avoid it by all means.
You could switch to HTML instead. There is a wonderful CodeProject article offering rendering of a HTML document in Forms:
A Professional HTML Renderer You Will Use[
^].
—SA