Unfortunately, plagiarism is the most serious offense on this forum and just apologizing for it will not help you.
There is a very small chance that the admins will forgive you and remove the permanent ban on your account. For that to happen, you would really have to have an account that has a notable role and importance for this forum and you have only been a member for a few weeks and have only written a few posts.
Many banned members have tried this but failed.
Snowpega gave you very good advice, forget about this old account and start over, this time respecting the forum rules and without plagiarism.
You are correct here, the chances are really higher that the admin will not allow OP's old account to post again.
As Plagrisim is a great example of shit-posting, and it is just a useless weight on the forum, which just overloads it in my point of view.
So, in case the OP wants to share something plagiarized, then I would really advise him to share a reference to that content and only share if it is something important, helpful, or informative. Other than this, this behaviour will not be acceptable in any way. I have seen many accounts being banned due to plagiarized content that also doesn't share a reference to the original content.