National Digital Library
National Digital Library of India (NDL India) is an all-digital library that stores information (metadata) about different types of digital contents including books, articles, videos, audios, thesis and other educational materials relevant for users from varying educational levels and capabilities. It provides a single-window search facility to access digital contents currently existing in India as well as other digital sources under a single umbrella.
https://ndl.iitkgp.ac.in/
Project Gutenberg
Project Gutenberg offers over 57,000 free eBooks. Choose among free epub books, free kindle books, download them or read them online. You will find the world's great literature here, with focus on older works for which copyright has expired. Thousands of volunteers digitized and diligently proofread the eBooks, for enjoyment and education. No fee or registration is required.