If you were to chop off Genesis 1–5, you would not be able to competently answer this about the instructions and teachings of the Father and Messiah: “Why should I do that?” Two-thirds of children from Christian homes will walk away from their faith to varying degrees, and one of the main reasons for that fall off is they are not given honest answers about the authority of the Scriptures.
Some Bible versions translate Gen. 1:1 as “In the beginning, God created…” or “In the beginning of God’s creating the heavens and the earth….” בְּרֵאשִׁית Bereysheet (Genesis) is not a science book. It is not designed to teach you how God created anything. The purpose of the beginning of Bereisheet is to teach us who God is, what He did and how powerful He is, much like Devarim (Deuteronomy) starts with reminding the people who God is and why the Ten Commandments say to have no other gods before Him.
Each one of the patriarchs listed here are listed for a reason: to show us where Noah came from. Each one of the these patriarchs had other sons and daughters besides those mentioned here, but God singles out these particular men to teach a specific lesson.
The lineage represented in Genesis 5 are the leading righteous figures before the flood. The names of these men can teach us about the working of God in a world much like our own, growing increasingly dark as judgment approaches.