Shan Hai Jing is the first book in ancient China? Are there any books written before it? In which ancient books are Huangdi and Chiyou described in detail?

No, Shan Hai Jing is a book that records China's myths, geography, plants, animals, minerals, products, witchcraft, religion, medicine, folk customs and nationalities. From the early Warring States to the early Han Dynasty, it was written by Chu people and Bashu people. Scholars in modern China generally believe that Shan Hai Jing is not a temporary work, and its author is not one person. It's an ancient absurd fairy tale. It was compiled by Liu Xiang and Liu Xin in the Western Han Dynasty. Shan Hai Jing is China's first book! Books with detailed descriptions:

Shangshu, Warring States Policy, Yizhou Book, Zhuangzi, Liezi, Historical Records and Lun Heng.