Q. 1. Since Jesus was God, how human was He? There must have been some things that He did not have to learn as a child.
A. 1. The Catholic Church teaches that Jesus was both, fully human and fully Divine.
In the Letter to the Colossians, verses 2:9, we read "For in Christ all the fullness of the Deity lives in bodily form..." In other words, in Jesus the Divine fullness of God lived fully in His human nature.
Accordingly, like any newborn infant, Jesus had to be taken care of by Mary and learn the skills of walking, talking, reading, jumping, dressing, playing, etc... Jesus was not born as a superbaby, nor have infinite knowledge in His human nature.