I need the what,why,when and how of the starting of the Old Testament and not just Genesis 1:1?

Sounds like you, unlike most with "questions", have a real question.

First of all, the oldest book in the Old Testament is Job.

The Bible Timeline Part 1 indicates Job was born around 2400 B.C.

Note: This Timeline estimates that, if God created the world in six twenty-four hour days and Genesis up to Abram in Chapter 11 is accurate on years, then those six days occurred slightly before 4156 B.C. Many estimate that the first day of creation was October 23, 4004 B.C.

The author of Job is assumed to be either Job, Elihu or a third person who lived back then. Many believe that Moses, while he was leading Israelites to the Promised Land (1510 - 1470 B.C.), took the book of Job, written in Aramaic, and rewrote the book in Hebrew.

Moses is regarded as the author of Genesis, Exodus, Leviticus, Numbers and Deuteronomy. Also written between 1510 and 1470 B.C.

Certainly, the first five books listed above (also called the Torah and the only five books that some people read as God's Word) were written to record history.

What led Job or Elihu or a third person to begin the writing of the Book of Job may have been the fact that Job felt that his life fell apart (chapters 1 to 3 show this), the three other men that spoke to him (chapters 4 to about 38) not offering much help, God spoke to Job thereafter and Job received back from God about twice as much as he lost financially and in children.