Most of the patriarchs and prophets never actually existed, so abrahamic religion is automatically man-made mythology.
A few that existed:
* Baha'u'llah - a follower of a Persian merchant called the Báb who had been going around preaching that god would soon send his messiah. The Baha'u'llah started a splinter cult in which he was the promised messiah, the reincarnation of Jesus and Muhammad.
the Báb - the aforementioned guy going around preaching that he was the reincarnation of Elijah clearing the way for the messiah.
Joseph Smith - a guy with a criminal record in fraud who claims to have found golden plates that came from the original native Americans, Egyptian speaking Hebrews.
* Muhammad - much of what is said about him is myth but he is the central figure of the rise of Islam, who was illiterate and did not write the Quran himself, with his followers claiming to speak for him.
* Paul - a persecutor of Jewish Christians who starts his own brand of Christianity suitable for gentiles and writes many letters establishing his theology.
* king Hezekiah, his immediate predecessors and kings that existed after him, such as the Maccabeans
* king Pekah of Israel and his immediate predecessors
Almost everyone else is a mythical figure or unrelated directly to the people who claimed to be the chosen ones, based on a covenant between Abraham and God. All but the kings claimed to have a direct connection to god either directly or through angels like Gabriel, Moronai, and Jesus. Paul refers to Jesus as an angel in Galatians 4:14, so all of these people claimed to get truth via angels.
Everything written about Jesus pertains to a dozen other people, demigods, and an esoteric understanding of old testament prophecy from his birth to his death to the city he was raised to the city he was born to the miracles he performed. The Quran already questions the crucifixion, but now he does something even more miraculous by ascending into heaven without dying like Elijah or Enoch. If there was "some guy" behind the myths you can't establish what that would be with any certainty as the text allows for multiple rationalizations of him from an apocalyptic rabbi to an exorcist to a lunatic preacher. None of these ideas lay credence to him being the divine son of God or the chosen messiah. This really only presents a problem for Christianity and Islam, though, so we need to delve into the old testament, because even Baha'i uses their existence as well as the existence of Krishna and Zoroaster to justify the messengers of God which it is based upon. Judaism and Samaratinism disregard the new testament, Quran, Upanishads, and other religious books as being divine scripture.
Elijah - name means "Yahweh is my god" - a mythical prophet who performs many miracles to combat polytheism and is taken up to heaven in a whirlwind.
David and Solomon - mythical or insignificant rulers as Jerusalem was a small village during the time they were supposed to reign. Given biographies to establish Israel and Judea as two parts of an otherwise unified kingdom. Almost nothing to back up their existence except for a stele from the time of Hezekiah that puts him within the "House of David." The majority of the old testament besides the prophetic literature and the works traditionally ascribed to Moses are based on these two mythical kings.
The judges - any that existed were various tribal leaders trying to hold a society together after the Egyptians abandoned the area of Canaan following th battle of Kadesh. Samson is a clone of Hercules and acts like one of various models for the promised messiah, which Jesus copies, but in an updated form.
Moses - the patriarch who led the Israelites out of captivity in Egypt while performing miracles, getting laws from atop a volcano, and speaking to a burning bush. This character introduces Yahweh into canaanite polytheism and copies Sargon of Akkad and Hammurabi. The reality of the situation is that Egypt was spread across the Levant all the way to the Hittite and Assyrian Empires so there is no logic behind the story about escaping Egypt to go to Egypt after getting lost for 40 years in the desert. The books generally ascribed to him were written over the course of multple centuries and borrow a lot from surrounding religions. In some stories Yahweh is just a jealous god among many gods and in others he is the only god there ever was. These stories were not written by Moses, the narrative is illogical, and he is a rip off of mythologic stories written about two historical kings in Assyria dropped into a narrative about Israel's struggle with the Egyptians that never happened.
Abraham - depending on the source he is a representative of the entire land of Canaan and a pact establishing a covenant where the Israelites would be given the promised land as long as they obey the rules imposed by the priestly sect which they claim came from god. At least one guy sees him as a patriarch who actually existed but the Lord he made a pact with was a Babylonian king such as Hammurabi. Otherwise, there is nothing to suggest he was a real person, and was actually just a representative of the chosen people. In judeo-christian religion they trace this back through Isaac, while the Muslims go with his other son who was cast into the wilderness, Ishmael. Whichever son is seen as the way in which the chosen people would be declared have Abraham nearly murder him upon the alter and his life is replaced with a lamb instead leading to the Jewish Yom Kippur rituals and the move away from human sacrifice that the christians return to with Jesus. Jesus is this lamb and you no longer have to make animal sacrifices on an annual basis.
Noah - unless you are a young earth creationist, you're aware there was no global flood and that Noah is just a rip off of Utnapishtim, Ziusudra, and Atrahasis. Everything that occurs before or immediately after Noah is from Assyrian and Babylonian mythology as well. This includes the creation narratives, the garden, the promise of eternity that humanity failed to obtain, a global flood, and the confusion of language atop a tower dedicated to Innana and Marduk. Interestingly enough, Inanna is also the oldest idea of a child of God who descends into hell, has her dead body hung on a wall, and is revived from death via food offerings. Obviously not identical to Jesus, but died, gets crucified (hung up), raises from the dead, ascends into heaven, and shares victory over death through baptism and communal food gatherings.
Tracing everything towards the origins of this type of monotheism drops it square in canaanite polytheism heavily influenced by Mesopotamian polytheism, in a region subordinate to Egypt, which establishes itself as a strong kingdom until they are destroyed by the Babylonians, Persians, Greeks, and Romans gaining theological attributes from their oppressors all along the way. This leads to the monotheistic nature in all of them, the apocalypse in Christianity and Islam which came from Zoroastrianism, the dying and rising child of God found in Christianity rejected in Islam, and various other ideas that leads Baha'i to come to the exact opposite conclusion as what I've found.
Religion is a man-made construct to describe the world and control the subjects based in ignorance, metaphor, and magic. Over time religions evolve to fit the cultures in which hold them in high regard. In the last 200 years a resurgence in literalism and death cult behavior has led to Mormonism, Bábism, and Baha'i to modernize mythology and make excuses for the obvious problems while creating new ones of their own.
The few people that did exist listed first merely follow the same pattern of a man who was all by himself and gets divine information from an angel before his teachings are written down as theology. At first there will be a very small following but as the religion gains traction it grows in popularity and employs various methods for keeping those in power prosperous and remembered as time goes on, with no real justification for the lies and empty promises along the way.