I don't think you can delete your account, so you can try to forget about it, or you can delete all your login details so you can't log back in. It seems like you've made a mistake on this forum, and I'm guessing that's why you want to delete it, right? If so, I think it's pointless, because all your activities are recorded, so it will be a penalty for your negligence on this forum. I think some other people (especially newbies or beginners) need to learn from this incident how important it is to keep your account safe by following the existing rules.