As odd as it may sound, for many years, skeptics and scholars alike have questioned whether there was a real person named Adam in the history of the world. They go as far as to suggest it was only a story (“Once upon a time…”) or an allegory (standing for something else).
Bottom-line: Affirming the historical existence of Jesus Christ is contingent upon affirming the historical existence of Adam. If I don't believe in the historical Adam as the first man, I'd be consistent not to believe in the historical Jesus as the second Adam. To be consistent, if you don't affirm the historical Adam you need to erase the genealogy of Jesus (Luke 3).
While Christians might hold differing views regarding the age of the Earth, the question of Adam's existence remains a fundamental concern within the context of the gospel.
What does the Bible say about this?
--Jesus believed in a historical, real Adam (read Matthew 19!). Therefore, the matter pertains to Christology. If Adam and Eve were not factual historical individuals, then it leads to either 1) the conclusion that Jesus deliberately misled us or 2) the implication that Jesus lacked knowledge. What’s more, Jesus accepted the Scripture as the Word of God. He called it “the Word of God” (Mark 7:13) and “the commandment of God” (Mark 7:8).
Jesus acknowledged the historicity of the individuals and incidents recounted in the Scriptures, including Adam and Eve, Noah and the flood, Lot's wife, Jonah and the large fish, as well as Satan during His moments of temptation.
--1 Chronicles 1: Has no problem addressing Adam as a historical figure.
--Luke 3’s genealogy: Adam is listed alongside Jacob, Isaac, Abraham, Noah, Seth, and God himself as being historical. An element of Luke's intention in offering this lineage is to demonstrate that Jesus, whose lineage can be traced back to Adam, possesses the eligibility to serve as the Redeemer for diverse groups of individuals. This message is rooted in Luke's belief that all humanity can trace their ancestry back to Adam.
--Acts 17:26: “And he made from one man every nation of mankind to live on all the face of the earth, having determined allotted periods and the boundaries of their dwelling place.”
While Paul doesn't explicitly mention Adam's name, he bears witness to the universal origin of humanity from a solitary individual, who he understood to be "Adam" (Romans 5:12–21; 1 Corinthians 15:20–22, 44–49). Moreover, Paul's discourse concludes by focusing on the "man" resurrected by God, who will ultimately judge "the world" in the culmination of time (Acts 17:31). The singular figure, Adam, forms a natural and anticipated contrast to the singular figure, Christ Jesus. Just as humanity originated from a man, the world's judgment will be carried out by a man. Therefore, the "one" mentioned in Acts 17:26 must signify Adam, the forebearer of every human being.
-- Paul believed in a historical Adam (Rom. 5:12-21; 1 Cor. 15:21-22, 45-49). Without this teaching, the doctrines of original sin and guilt are no more. So, also, is the doctrine of the Second Adam (Jesus).
This presents a substantial dilemma. At this juncture, you are essentially making a decision to either have faith in the Bible or not. If you choose not to have faith there, it opens the door to potential disbelief in various other passages, especially those that might be challenging or deemed inaccurate by certain philosophers or pseudoscientists. This could lead down a significant and treacherous path of skepticism.
When we disconnect theological beliefs from their historical foundations, they become easier to fit with other information and ideas. Some beliefs don't rely on history.
I believe that the idea of Adam and his role as the first human ancestor are not beliefs that can easily be separated or changed. The fact that Adam actually lived is really important for keeping a Christian explanation of bad things and wrongdoing, a Christian view of God, and the reasons for Jesus coming, dying on the cross, and coming back to life. The idea that Adam is like the father of all people helps to keep things fair when God holds us responsible because of Adam (and, by thinking about it, fair when God saves us through Christ). This idea also keeps the sense in the story of Jesus coming in human form. Changing either of these beliefs would have very serious results.