I have heard or read this question: is Genesis 1-11 different from Genesis 12-50?
It’s usually asked by those who, unlike me, hold to a young earth view of creation. That is, people who think the days of Genesis 1 each refer to a day of 24 hours.
The question is asked with a subtext: that people like me read Genesis 1-11 in a different manner from, say, the account of Isaac. And that this is a wrong thing to do, unjustified by the text.
Here’s one part of an answer. Yes, Genesis 1-11 is different.
And the Bible itself shows us this. In particular, the Bible frequently refers to ‘Abraham, Isaac and Jacob.’ Even in Genesis itself (eg, Genesis 31:53, or 50:24). These three are the patriarchs whose lives the Lord works through – despite themselves, it often appears! – to bring blessing back into the sinful world. These three are frequently linked, right into the New Testament (such as Matthew 22:32, Acts 3:13).
In contrast, I’ve never come across a biblical phrase linking, say, Noah and Abraham.
So: there’s certainly a change at the end of Genesis 11. There’s biblical reason to view this as a different stage in God’s unfolding plan.