Fate and free will are major topics in Paradise Lost. God reveals that he knows what will happen to Adam and Eve, but resolutely denies that there is any such thing as fate. Huh? God knows what will happen (that Adam and Eve will disobey him) just like we know the sun will rise tomorrow. So it might seem sometimes like Adam and Eve never had a chance, but according to Milton, that's just not true. After all, it's not God's fault that he can see everything that will happen as if it has already happened!
Predestination and foreknowledge are not the same thing; Milton's God makes that very clear. At the same time, by putting the forbidden tree in the garden, God plays some role in the Fall.
Although Adam and Eve were given freewill, their marriage involves a good amount of subjugation that contrasts markedly with God's emphasis on freedom.