To unsubscribe to a particular forum or topic, open your profile, then click on Subscriptions. Then click on the title of a forum or topic. You should then see a choice to Unsubscribe.
At that point, you should no longer receive any emails from the forum.
We currently have no specific mechanism to automatically delete your whole account. And if that is what you really mean, then this is a new first for us. We’ve never had a request to do this before.
Because this is a forum with replies that might be useful to other users, we would prefer to not delete any of your content.
I believe we could possibly delete your entire account while assigning your posts to an anonymous “user”.