As to the historical validity of the biblical Moses there are significant historical, textual and archeological challenges. There have been many attempts by Christians to come up with a coherent narrative for the biblical Moses that works. The basis for disputing the Historicity of the Moses story focus on 4 categories. These include timing (when could the Moses story take place). Next is scope - 3 million people. Next is writing and the last is the hedgenemy of Egypt.
Timing. Christian theologians place Moses from 1,500 BC to 1,200 BC. Unfortunately, Egypt ruled Canaan during this time. For most of the period they had regular military posts scattered around Canaan with most of their settlements in the coastal lowlands with Gaza as the administrative center. This is also the time when we have the Amarna letters. These are letters on clay tablets written in cuneiform written from the petty kings of the Canaanite city states asking the Pharaoh send them a few archers to put down upstarts and petty disputes. There are 382 known clay tablets recognized as the Amarna Letters, which constitute the official diplomatic correspondence of 14th-century B.C.E. Egyptian pharaohs Amenhotep III and Akhenaten. Moses and his millions had not arrived. The entire population of Canaan at that time might have been 50,000 - 100,000.
The Hebrew bible indicates that the Moses led wanderings could not have happened earlier than 1,200 BC. . In Genesis 13:17-18 “When Pharaoh released the people, God did not lead them by the way to the land of the Philistines, although that was nearby, for God said, “Lest the people change their minds and return to Egypt when they experience war.” So God brought the people around by the way of the desert to the Red Sea, and the Israelites went up from the land of Egypt prepared for battle.” The Philistines arrived on the coast of Canaan in about 1150 BC. They were a component of the Sea People who played an important role in the Great Bronze Age Collapse of about 1250- 1,150. Thus, God warned Moses to avoid these Philistines who arrived during this period.
Scope. The arrival of 3 million Egyptian former slaves into Canaan would have met with the Egyptian army. However, the Egyptians who should have known there were 3 million escaped saves headed to Canaan, did not increase their soldiers in Canaan as would have been expected. Egypt had as many as 1,000 soldiers scattered across their 3 strategic sites in Canaan at that time.
Writing. Canaan did not have a literary written language. Egypt had Hieratic as their literary written language prior to the conquests in Canaan. In Canaan/Israel early transitions between Egyptian which was an African derived language and hebrew developed which was a semitic language. The Israelites demonstrated an ability to write literary Hebrew around 800 BC. long after the events of and life of Moses.
Hedgenemy of Egypt - Egypt had conduct significant military battles across the northern part of Canaan such at Megiddo. Strategically, the only large competitor of Egypt were the Hittites of central Turkey. This Egypt kept most of their forces in Canaan near the northern border to protect against Hittite expansion beginning around 1,600 BC. Egypt regained its hedgenemy over Canaan/Israel until they were replaced by the Assyrians for 100 yrs. Then the Assyrians left and Egypt again took Israel into its empire.
Yes, the Romans were taxing, and years later the Muslims were taxing unless Jews and Christians converted. Not sure how many converted, how many were killed and how many did not convert and hated the taxers.
Yes, the Greek language, the Pax Romana and Jewish congregations in the area aided Paul's missionary efforts toward Europe.
It is unfortunate that Jesus did not commission other apostles who were as effective in the other directions, so there would not have been the spiritual vacuum that allowed Mohammed to do his thing.
Yes, Jewish history and the history of the Bible was like making sausage, with many unanswered questions, including the date of the time when Moses led the Hebrew slaves to Canaan, with 1,500 to 1,200 BC being the best bet. The ninth pharaoh of the New Kingdom, Amenhotep IV or Akhenaton (1369-1353), is noteworthy for attempting to change the Egyptian religion to monotheism, which is called the “Amarna Revolution”. (At this time records speak of Hittites gaining control of Syria and Habiru penetrating the area around Jerusalem.) Reactionary forces ousted the heretic pharaoh and began the 19th dynasty with the one-year reign of Ramses I, then Seti I (1302-1290), whose son, Ramses II (1290-1224) is thought by many scholars to be pharaoh during the Exodus led by Moses.
Certainly the Exodus would have occurred no later, because there is a stele erected during the reign of his son about 1220 that refers to a defeat of Israel in association with other Canaanites. I note that you cited the reference to the Philistines in Genesis 13:17-18 and said the Philistines (a component of the Sea People) arrived on the coast of Canaan in about 1150 BC.
Regarding the number of Hebrews who exodused, I began this computation but did not finish it:
1. Begin with 70 people who moved to Egypt at the time of Joseph, including at
least 12 couples (24 parents).
2. Second generation in year 20 = 190 (60 new couples) if each couple averaged 10 kids (+ 46 non-parents) ]
3. Third gen in 40 = 890 (600 newbies + 120 parents + 24 grandparents + 46)]
4. 4th gen in 60 = 3,720 (3,000 newbies + 600 parents + 120 grandparents)]
5. 5th gen in 80 = 15, (15,000 newbies + 3,000 parents + 600gp) ]
6. 6th gen in 100 = 93,000 (75,000 newbies + 15,000 parents + 3,000 gp) ]
7. 7th gen in 120 = ?
8. Etcetera ? [Not sure if that is 3 million.]
After losing many soldiers in the Red Sea, the Egyptian army was discouraged from chasing the Hebrews into the wilderness. I note that you said Egypt kept most of their forces in northern Canaan to protect against Hittite invasion beginning around 1,600 BC.
Moses would have had an Egyptian education and written language. I note that you said the language transitioned from Egyptian to a Semitic language by around 800 BC.