does he use a smart speaker?
Alexa or Google Home are so useful for everyone, but they do many things of use to a bVi person.

Look at MaxiAids. They have all kinds of stuff to help with independent living with vision loss.

What about braille measuring cups?

Or a braille watch so he can read the time without any noise.

Honestly, the best gift you could probably give him right now is a lot of patients. he’s probably going to be tripping over, bumping into, knocking over… remind mom to push chairs in, keep doors closed, don’t leave stuff out where he can trip over or where he can walk into… stuff like that can be just as valuable as any gadget. it is definitely not fun cracking your shin on an open dishwasher or your face on a cabinet door. if your dad likes to read, try getting him set up with The MLS/bard/Audible/bookshare services. That’s one of the things I often read about older people being afraid of when they lose their vision. Not being able to read anymore. That’s really not the case nowadays. Rare is it that I can no longer find a book in an accessible format. be it through one of the services I mentioned before or even through OverDrive or Amazon Kindle. I do the majority of my reading/listening through my iPhone, but there are standalone devices like a victor reader stream as well that may work for your stepdad. good luck.