If you are looking for a single Hinduism Holy Book like the Quran or the Bible you will be disappointed. Hinduism is not a scripture based religion. It is not a religion in the conventional sense. It is a way of life. Hindu religion too has innumerable holy books. The essence of it all can be summed up in ‘Tat Tvam Asi’ – Thou Art That.
Holy Books in Hinduism are
The Vedas – Rig Veda, Yajur Veda, Sama Veda, and Atharva Veda (Teachings from Vedas)
Upanishads, which are part of the Vedas, contain the core teachings of Sanatana Dharma (Hinduism) (Teachings from Upanishads)
Bhagavad Gita, the most popular scripture in Hindu Religion. (Bhagavad Gita Lessons)
Ramayana and the Mahabharata – How to follow Dharma? – the Hindu way of life is explained in these scriptures.
Puranas – Hindu teachings narrated through stories and incidents in them. (Teachings from Puranas)
Yoga Vasishta – Conversation between Lord Ram and Sage Vasishta. (Gems of wisdom from Yoga Vasishta).
All these scriptures together contain millions and millions of words. But they all suggest the same thing.
Follow Dharma. How to follow Dharma?
By understanding that the Supreme Truth (God) resides in all animate and inanimate.