[aknftech]

I can't imagine how hard it is to keep positive in this situation and I think it's great that you're asking these practical questions to help your future self out. I hope you get some really useful answers from the rest of the community.

I don't have the answers to those questions but I did want to drop a line of encouragement and say this; your hard work up until now will not be wasted, whatever you end up doing. You can — and will — find ways to continue to stretch and apply your engineering mind, and most likely in ways that you can't predict right now.

Later on, you will look back and find that nobody would be better placed for whatever you're doing at that moment than you.

Finally (and I'm not saying this to deter you from continuing down the SE route, there are plenty of examples online of partially-sighted or blind SEs doing very well and you're attitude is indicative that you should experience no different), but everyone of us has so much more to give to this world than just our skillset, and you don't need a qualification for the things that truly matter in life.

Keep going and I echo the other commenter, take car of your soul, it's important.