How to get legal safety after 45 years of child lifting?

Now a 45 years aged person who was actually child lifted while months old. In later years as a grownup inspite demanding for the background from the child lifters they never revealed the fact and keep making stories. From childhood times was stopped whenever tried to leave these people and after these many years when want to move away as an independent to know the background origin, these people simply seem to stop by claiming as one among themselves. Also believe if move away without any legal procedures could turn the story the opposite as one of their member is missing or absconding. What could be the needed legal procedure and approaching whom could be right to prevent any future trouble?