Plenty!
We see that Cain and Abel offered sacrifices. How did they know to do that? Or what to offer?
Cain was punished for killing his brother, but the Bible up to that point records no such prohibition.
Enoch “walked with God”. Where did he learn what behavior would be considered righteous?
Exactly. How about Adam and Eve? They leave the garden as practical naïfs, wholly unskilled in basic survival, and are able to survive. Clearly, they received more instruction and guidance than contained in Genesis.