|"This IP we are configure our own dynamic site"|
What does this mean? Makes no sense to me
"nobody can access our web site but the same time we are access the web site through PC IP the site will be opened"
Again the words and sentence structure tell me nothing
I suspect you are hosting a web site internally. It may appear you can access via the lan but not the wan.
Is this the case?
BTW quite messing with the server/tcp-ip. You are only muddying the waters. First step is to CLEARLY define what works and what does not. Then we can move on to the why.