There's a couple of free forum softwares that can be installed under your cPanel (Fantastico De Luxe, I think). PHPBB and SMF are offered there, but you can also install MyBB.
You can easily install a forum through cPanel as mentioned above, but in order to make it match the rest of your site you'll have to edit / create themes for yourself. Sadly there's not much you can do about this.
You could also try to mess around with the php coding and make the forum tables display in your template. But that would create too much work if you didn't really like the layout.
best way is to goto freeforums.org register a forum of your, configure from control panel, have ur url from doamin.co.cc and here is ur free forum on web just paste the url link where you want ur forum.....
i kinda need the forum on my site... the only problem is template mismatch....
my theme does not match the site.. can u make a template in phpbb 3 for me... thanks