Yes, it is achievable to receive papers for any dog that is definitely already an adult, but the procedure could be far more elaborate and time-consuming than registering a Pup. Adult puppies might be registered by using a kennel club or registry, even so the operator have to provide documentation https://www.openpr.com/news/4286965/how-to-get-papers-for-a-dog-the-complete-step-by-step-guide