Try your best to ignore the cartoons and movies that purport to tell the account of Moshe (Moses). They take many liberties with the real record, imposing their own story lines on him. Important elements at the beginning of the book of שְׁמוֹת Shem’ot, also called Exodus, are God’s faithfulness to the promise made to Abraham that his descendants would face hardship but become a numerous people and blessing to the nations.
People find it easy to criticize Sarai and Abram for their impatience in waiting for the son God promised them, but our insight is simply nothing more than hindsight. We aren’t any smarter or more faithful to God than they were.
Apostle Paul used as illustrations the two women, Sarai and Hagar, and the covenants God made with their sons, Isaac and Ishmael. Once you transgress a covenant, you have no hope, unless Someone better than you steps in with a second, better covenant.