can you reverse an adoption by stepparent?

You may need to contact an attorney to actually see about the change on a birth certificate. You do have the right to change your last name legally if this is your main goal. Anyone can leagally change their name if they are adults. I see your are male and this might make you as happy as anything else getting you bio name back could be as much as you need for your heart. But if the brith certificate matters to you I would think there could be a legal way to do so---not sure? Good luck.