Wasn’t the Pharoah considered to be a god who owned all land in egypt and everyone in it (except for the priests, who were given special privileges), making the distinction between slave and free somewhat academic?
Slave or free, a complicated question. Roman slaves generally had more rights than American slaves. Were “free” men able to move from one village to another without higher level permission? What was owed to the state in labor and production by various strata of society? Were buried laborers/”slaves” more or less healthy/well nourished than neighboring villagers/farmers? All questions that can clarify the extent of slavery/citizenship.
So far as Moses and the slaves, that was a much later period of history. The pyramids were more than 4000 years ago before the chaos of the First Intermediate Period. Google Ipuwer papyrus. Abraham and the subsequent migration into Egypt was after the FIP, perhaps because of the FIP. Who knows what changes might have taken place in the 3 or 4 hundred years after the first of Abraham’s people settled in Egypt. They might have become so numerous that it awakened jealosy. Also the exodus period was probably after the Second Intermediate Period, and the Hyksos (shepherd kings) period in Egyptian history. Were they relatives? and subsequently despised?