https://www.amazon.com/Buddhas-Words-Anthology-Discourses-Teachings-ebook/dp/B003XF1LIO
one of the best single books written on early buddhism
also this
and this is, basically, "early buddhism" practiced in the modern age by the greatest modern master of Theravada buddhism
Buddhism is divided into 3 schools: Theravada, Mahayana, and Vajrayana ("Tibetan" ).
Each school has their own set of writings, beliefs, rituals, and customs.
A lecture from the Buddha is called a "sutta" or "sutra".
Theravada is the oldest surviving school of Buddhism and has the oldest collection of suttas called The Sutta Pitaka.
Ancient Pali doesn't not translate well into contemporary English.
It is very easy to misunderstand the translations and not even be aware of it.
People new to Buddhism are better off starting with reading what other people wrote about the Buddha's teachings.
"What The Buddha Taught" by Walpoa Rahula, a Buddhist monk is an excellent book. It is clearly written. It is short.
There are thousands of suttas and it can take years to read them all.
Fortunately, there is a lot of redundancy in regards to the suttas. Anthologies taken from the Sutta Pitaka can represent the Buddha's teachings quite well and with more brevity.
"Word Of The Buddha" compiled by Buddhist monk Ajahn Brahm is only 69 pages long.
"In The Words Of The Buddha" compiled by scholar and Buddhist monk Bhikkhu Bodhi is about 512 pages long. In addition to more sutta excerpts the reader gets Bhikkhu Bodhi's expert explanations of the meaning of the suttas.
Lastly, the entire Sutta Pitaka can read online or downloaded for free, legally, into eBook from SuttaCentral.net.
This is as close as it gets to a bible version:
https://www.amazon.com/Buddhas-Words-Anthology-Discourses-Teachings-ebook/dp/B003XF1LIO