He must learn to use a smartphone with screen readers. That will open up lot of dorrs and options. It's very much possible for old people to learn that.
The national Association of Blind in Mumbai, NFB in lot of states, records and hosts an online library of lot of audio books. Bookshare.org is also an option. There are blindness related organizations all over India, probably get in touch with the nearest one, they will help, they will also teach him how to use smartphones and stuff.
Alexa also works, but for basic settup, it's good if your grandpa can oporate a smartphone. I suggest an IPhone, and learning resources from
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