How do I create site Forums??

Like PHPBB3, IPB, Vbulletin ? PHPBB3 is free you can download it unzip it upload it to your site via FTP and start installing it .. but have an database setup so that it can store all the posts comments .. PHPbb3 will auto add the stuff for you so you dont have to do much

SMF is also a good forum. Make sure you set the title of the folder to index.html for an easy setup.