History is not my area of specialization. I am curious to know about the historicity of Moses and Abraham from the viewpoint of modern critical scholarship. It would be great if references are provided.
When considering historicity, Abraham, Jacob, and Isaac have traditionally been considered together as the "patriarchs". There used to be some historians who seriously argued that they lived during a patriarchal age sometime around 2000BC.
Today the stories they are contained in can fairly reliably be placed as written in the near east Iron Age, which is roughly a millennium after they are set. So either they were flat out invented at that time, or there was an oral tradition for that long that changed drastically to include Iron Age elements (and would presumably have changed just as drastically in less noticeable details as well). For that reason, they simply cannot be considered historical figures.
Moses went through a separate analysis, but the result is roughly the same. The texts that mention him are accepted to have not been written until the Babylonian Exile (late 6th century BCE) whereas the event itself would have occurred 700 years earlier. There's no real corroborating records of such a thing from any other sources, and the linguistic evidence is most consistent with the Hebrews being closely related to their neighbors in the levant, not recent immigrants from elsewhere.
The Babylonian Exile of course was a time a great stress, when a tale about how they persevered as a coherent people through slavery and exile would have been very helpful, and Egyptians a very convenient bad guy that their Babylonian masters would not have complained about.
That shouldn't be taken to lessen its impact one iota. You'd be hard-pressed to find any story more historically important than Exodus. It was likely designed for resistance. Enslaved people have used it for inspiration and comfort and resistance ever since. It was a rare speech from Martin Luther King that didn't reference it.