Why those hundred? Why not some other hundred? In other words, what is the selection criteria?

Is it necessary to read those hundred books? Why? Are they reference books or story-books?

If reference books, do you need to read the whole book or just the relevant parts of it?

If story-books, what is it you want to discover? The actual story, or the style of writing? Again, do you need to read the whole book or just the relevant parts of it?

Does it have to be a physical book you read? Could a summary do? Many books are reduced to a short summary of the storyline in Wikipedia. Could a movie or documentary do? Could an audio-book do?

Regarding actual brain-input time. There are lots of times during the day when you have a few minutes available: on public transport; while sitting in the toilet; while relaxing before turning the light off at night; while eating your lunch; reading it off a computer screen; listening to audiobooks while driving, or walking, or resting.