Forget the video,
refer to Scripture instead...
Genesis 11:11... And Shem lived after he begat Arphaxad
five hundred years, and begat sons and daughters.
So when Arphaxad was born, Shem had
500 years left to live.
Genesis 11:12... And Arphaxad lived
five and thirty years, and begat Salah:
So when Salah was born, Shem had
465 years left to live (500
- 35).
Genesis 11:14... And Salah lived
thirty years, and begat Eber:
So when Eber was born, Shem had
435 years left to live (500 - 35
- 30).
Genesis 11:16... And Eber lived
four and thirty years, and begat Peleg:
So when Peleg was born, Shem had
401 years left to live (500 - 35 - 30
- 34).
Genesis 11:18... And Peleg lived
thirty years, and begat Reu:
So when Reu was born, Shem had
371 years left to live (500 - 35 - 30 - 34
- 30).
Genesis 11:20... And Reu lived
two and thirty years, and begat Serug:
So when Serug was born, Shem had
339 years left to live (500 - 35 - 30 - 34 - 30
- 32).
Genesis 11:22... And Serug lived
thirty years, and begat Nahor:
So when Nahor was born, Shem had
309 years left to live (500 - 35 - 30 - 34 - 30 - 32
- 30).
Genesis 11:24... And Nahor lived
nine and twenty years, and begat Terah:
So when Terah was born, Shem had
280 years left to live (500 - 35 - 30 - 34 - 30 - 32 - 30
- 29).
Genesis 11:26... And Terah lived
seventy years, and begat Abram, Nahor, and Haran.
So when Terah begat Abram, Nahor, and Haran, Shem had
210 years left to live (500 - 35 - 30 - 34 - 30 - 32 - 30 - 29
- 70).
(Note: I agree with most scholars that verse does not mean that Terah had triplets. Rather, that is when he began to have those sons.)
What it does mean is,
according to Scripture...
Unless Terah (Abraham's father) was
OVER 280 years old when Abraham was born...
Shem was alive when Abraham was born (and even when Isaac was born).
Here is a
Bible Chronology from Creation to the Battle of Qarqar along with the Scripture references.