I hope this doesn’t happen to you. I can’t answer your question about Braille but I would really recommend that while you have sight you learn how to operate an iPhone (if you can afford one) with VoiceOver. You may read books in Braille but you’ll also want to be able to use a phone.

Have you had a lumbar puncture? Either of those could be causing excess spinal fluid which is actually how I went blind.

Personally, I would recommend at least learning basic, also known as grade 1, braille. It's useful for labeling and typing on the iPhone, at least.

I'd also recommend starting basic screen reader training while you can see. I'm personally very comfortable with apple devices, but just about anything has at least one.

I use Braille the whole time. I have a Braille screen reader and a Braille notepad. If you embrace it then it becomes easier to study communicate and generally survive.

If only one eye is the problem, then no. People who have monocular vision function pretty normally. I am also a believer that it is best to learn Braille when you actually need it. You can pick up grade one Braille pretty quickly if it becomes necessary. You did not mention a cane or mobility training. If you are expected to have a severe visual loss. A cane will be extremely useful. Even if the cane is just so others know you are visually impaired (crossing streets, using public transportation etc). My 2 cents.

Just gonna echo what other people have said, at least learn grade 1 braille as well as learn how voiceover works.

Learning grade 1 Braillle may help you, although there are free screen readers like NVDA and Voiceover that will help you a lot more in my oppinion. Braille is good as it is on some things here in the UK but if I didn't have to use it and just rely on screen readers, I'd be happy to do so. Although reading something without my phone is sometimes rewarding. SO it's up to you, do you want to learn braille now, when you can see and might use your eyes for it instead of your hands, or would you rather use TTS and screen readers where you must use your hands to use the laptop/PC/phone?