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With regard to a forum module, and most other types of modules you'd be likely to use, you can configure them in such a way that each group has access to different forums (or different news topics, or different downloads categories, etc).
That's all done by setting up the groups you need, and then creating topics/forums/categories/whatever for each group, and then assigning permissions appropriately so the right groups only see their own stuff.
Depending on the complexity of your group structure, this can become a management challenge.
To actually duplicate modules, so you have more than one copy of the same module in your site, check out this FAQ:
https://xoops.org/modules/smartfaq/faq.php?faqid=274I don't think that's really what you're after though.
Good luck,
--Julian