BlogSpot (www.blogger.com) does not provide the option to remove the Copyright tag or Credit line. They show a link at the bottom.
I can help you to remove "Powered by Blogger" text from themes. Are you interested? Hire me!
1. If your site is built on BlogSpot, then order only.
2. I will provide service for one issue in one site for one time with this service.
3. I am not interested to provide services for any site which contains unlawful content, hate speech, nudity or adult item.