register dog without papers

https://mydogcertificationpdfpath.ironwoodscope.com/posts/how-a-dog-certification-pdf-streamlines-foundation-registration

I found a stray dog and want to do right by him, but he has no tags, no chip, and I have no papers from a previous owner. I'm trying to register him as my own at the local shelter, but they're giving me the runaround because I can't prove where he came from. They want me to post found flyers first, wait a certain number of days, and maybe get a vet to vouch for his health. It feels like a lot of hoops, but I'm determined to give him a home.