That time-frame was based on the generations of names in their oral tradition. Only, some of those generations were way longer than any real humans ever live, while others are glossed over because so little is known about them, so the scribes' math it pretty screwy. That's not a criticism: every tribe makes up some screwy math and physics to explain its own origin.
(I am, however, extremely critical of modern people who try to impose those ancient stories on other people who know better.)
Where? In the Bible? Lots of nearby cultures are mentioned, but not in detail, since the Jews of that time didn't get close to any of the cultural centers. Probably, they got to the market at the edge of Damascus, Hebron, Tyre, Beersheeba, sold some bullocks, bought some fabric and olive oil, then moved on. They knew about Sumer, Egypt and Assyria, but not Greece or Rome, until they were conquered, and certainly not about India or China.
If the much-storied Abraham invented a whole language, 1. To whom did he speak it ? 2. Why would he need it? and 3. Why doesn't the bible mention it?
That's what i said. Some of the peoples in the region were like the Jews, more or less, while some were very far advanced beyond them.
The bible doesn't talk much about them, because it was never meant to be the story of mankind. The early parts were meant to be the story of the Jews - as they liked to tell it, from their own perspective, for their own self-esteem. The collection, and later parts, were meant for European Christians, to give a background and authority to their religion, which the Roman priests were constructing.
Abraham come from UR Chaldean an before the area was Sumeria and after Akkadian replaced them . The language I believe was Semitic , then Abraham moved among Canaanites, I believe the language was no muy different because Abraham dealt with Hittite also in the area by Hebron.
Beside each culture or tribu will recant verbally to ancestry about himself and not history of their neighbors unless there is some interaction like dispute . Let's look at the American history and how much details are written on colonizing the native American , even we had paper and pen and we had ability in reading and writing.