Adam,
Your post is not clear to me but if you are asking can you link from one page/assignment to another in Moodle, the answer is yes...as long as the person has permission to be on the page the link takes them to. If they don't have permission to be there, Moodle will generally tell them they are not enrolled and ask for an enrollment key.
I do this all the time. I have hundreds of tutorials all located in one location and dozens of assignments in various courses. Links in the assignments in the defferent courses, take students to the tutorial (books and wiki's) and on the last page of the tutorial, I have links to take students back to their respective course/assignment.
Having all the tutorials in one location means I only have ONE copy to keep updated even though the tutorial is used by defferent classes. It is a little extra work on my part to make and maintain the links, but having only one version/copy of a tutorial to update, makes it worth while.
Hope this helps,
AL