How to install a forum on your site?
Here he is

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Not sure of what your asking. Are you asking how to install a forum on your site?
I am guessing that your site is this:

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and your wanting to install a forum there.

If that is your question, then I can help you. There are a few options you can do. Since that looks like a basic HTML template, then that means your going to need to download and install just a plain forums system onto your site. This site here, is using a CMS and not just a forums system. A CMS is a all-in-one system which handles everything. But for a plain forums, your best checking out one of these three:

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- Large communi9ty and open source and all willing to help. You can get great support with them and very customizable and many free mods.

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- Another one that has been around for a while.

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- Don't know much about them except they have a open source version which is community supported.

With those systems, you can pick and choose one of them and install them onto your site, you will need to talk to them for support with that and integrating it into your site.
Just note that you will need a SQL database to be able to host the forums.

Hope this helps.