Is there anyone in Bitcointalk forum who tell me that how to delete bitcointal forum account?<…>
I assume you want to delete all posts and the account itself. You cannot delete your account.
At best, you can try to delete all posts that are deletable (not all are – depending on where they were published), or nullify (erase) their content.
Since your account is still a Newbie with low activity, I guess you could do something like plagiarize and then report the plagiarized post, which may get it Nuked. A Nuked account gets its posts deleted. I'm trying to find the exact activity limit for a Nuked Newbie.