The exodus occurred 430 years after the arrival of Jacob and his family in Egypt (Exodus 12:40) when Moses was 80 years old (Exodus 7:7). This means that Exodus 1:1–22 covers roughly 350 years, beginning with Jacob’s arrival (Exodus 1:1) and ending shortly before Moses’ birth (Exodus 2:1–2). Most likely, the decree to throw the baby boys into the Nile was made less than three years before Moses was born. After all, Aaron was only three years older than Moses (Exodus 7:7) but was not affected by this decree.1
Most of Exodus 1 deals with the oppression of Israel in Egypt. It is unclear how much time elapses between the attacks of Pharaoh, although it must have been substantial. For it would have taken several years for the Egyptians to realize that their attempts to control the population were failing.2
1 These are the names of the sons of Israel who came to Egypt with Jacob, each with his household: