Orientation and mobility training and therapy for starters. There are resources available that are willing to help as much as they can. He is still young enough for you all learn together so that's good. I hope other people have more advice for you. Good luck in the future.

If you can, I'd recommend finding resources to learn Braille. Even learning a little can help with daily tasks (you can get a Braille labeler for not too much money and label things around the house). There are now instructions for putting together select Lego kits using both Braille and text to speech. That might be a fun thing to try. If you are in the US check out bookshare.org. Anyone with a print disability can get access to digital versions of hundreds of books. Find a good text to speech program and practice using that to listen to books. If you have a Netflix subscription you can watch/listen to a bunch of videos that have audio description. Anything you can do to improve the ability to practice listening comprehension will help. I wish you the best of luck. And be sure to take care of yourself, too!

Have you talked to any service providers regarding training? You want to start early, they can learn a bit faster when they have some vision still. Additionally, you want to find out what kind of funding is available that can help (for tech and such).

Hi, in which state are you in?
There are some FB groups specific to the diagnostic.
I recommend joining the National Federation of the Blind. They have a division for parents and they provide a few programs for children.

Nobody has mentioned it yet, but your son is 13, which means he gets services through his school. He should get a functional vision evaluation, learning media assessment, and orientation and mobility evaluation done by trained professionals no later than 70 days after you make a request for it in writing if you live in the US. Be clear that your son has a degenerative disease and that you at least want to work on prebraille skills or a curriculum like I AM Able (It's like core words to your son's vocabulary in braille instead of being able to read on grade level in braille). Start introducing adaptive techniques now. Make it part of the routine. Ask the professionals who will be working with your son what you can be doing at home to help. Be very careful that you are building meaningful time at home for your son to learn to do new things on his own. It's going to be easier and faster to continue to do things for him, but you won't be doing him any favors. Expect more from him than what other people expect from him because he's capable of it. The NFB is a great place for setting those expectations.

I wouldn't invest in a braille machine just yet. The FDA has fast-tracked orphaned disease treatments involving regenerative therapies. That means that conditions that have no existing treatment get faster approval processes. The very first gene or cell therapy for a blindness condition was recently approved, it's called Luxturna. This is all possible because of a law called the 21st century Cures Law. There is a statistical likelihood that most forms of congenital **retinopathic** blindness and retinal dystrophy will be eradicated in the decade to come.

https://www.retinalphysician.com/issues/2019/march-2019/retinal-gene-therapies-in-clinical-trials

The process is moving so rapidly that commercial entities are already being founded to commercialize the treatments.

edit: a single word