Reading lots of books each year or perhaps a book a day is generally possible. Reading books (or ebooks) is and ought to be an educational, informative, and enjoyable experience. That being said, a number of factors ought to be taken into account or considered.
There are books consisting of a hundred pages (or less), and books with more than five hundred pages. Reading books with less pages takes of course less time and less concentration. There are short abridged versions and long unabridged versions. One could read an entire book, or read the first and last chapters with a few other chapters.
Some books about self help, self improvement, or giving advice are useful, others are not so useful.
There is quality and there is quantity. One could read for example dozens or hundreds of romance books or novels by unknown authors, or read books, novels, literary works and stories by great or historically significant authors or writers.
Reading and understanding for example a dozen or twenty good books a year by important and great thinkers, writers or philosophers, is more fruitful, beneficial, or thought provoking than reading hundreds of “ordinary”, unoriginal, or insignificant books.
There are types of books with topics requiring more focus, intellectual effort, or time, such as scientific books or books containing equations and formulas.
Concerning my own experience with reading books, when I was 14, going on 15, I took a step further from reading general cultural and literary books, and started reading important books about science, physics, and the philosophy of science. At the age of fifteen the authors I read included scientists and thinkers like Einstein, Henri Poincaré, Louis de Broglie, David Hume, and Kant.
I also read a few short books about astronomy and the various branches of physics, and continued reading such books in the following years whenever I had time.
When I read a book containing advanced mathematics, I sometimes had to wait until I was able to study these advanced topics and fill in the gaps in my mathematical and scientific knowledge. For example, after the age of 15 I had to wait a couple of years before I could study and understand well topics such as advanced calculus, complex analysis, and tensor analysis.
Moreover, one could read books in one single language or in more than one language. Some books may be read in English while being originally written in another language. Some other books lose some of their meaning after being translated; these are better understood when they are read in their original language. I can read books in four languages, and I’m still learning other languages whenever I have time.