But posts with web links to sites are often treated as spam so you have to be careful about the question and link.
I can't decipher your question but I'm guessing you want to run a forum at your site and write such using Wordpress CMS. Let's see if a google finds that.
https://www.google.com/search?q=forum+for+wordpress+cms and the first hit at http://codex.wordpress.org/User:Lastnode/Wordpress_CMS covers this very well about the issues.
As what I would write is duplicated at the two links I gave, I'll stop here.
I am using WordPress CMS to design my website and it's hosted in GoDaddy under a paid domain name that's why I am looking for a free forum to use it but under my website URL and my website design. please let me know which forum will fit my needs