What!?
No middle ground??
Oh! Now I can see where you're coming from. Wow.
Here's the thing. There have been all kind of outstanding people in this world, forceful personalities, charismatic leaders, who when they walked in a crowded room, people would say, "Who is he?" And that's the very nubbin of it all, the very question Jesus challenges us with: "Who do you say that I am?" (Matthew 16:15)
Jesus is the only person I've ever heard of, though, who was so compelling, so exceptional, yet so baffling, that everybody he encountered ended up asking, not just "Who is he?" but "WHAT is he?"
The rather astounding answer is that Jesus is one person who is truly God and truly Man, not 50/50 but 100/100.
You apparently have done some thinking about Jesus as Divine person, eternal, infinite, omniscient, and so forth, but have not quite grasped the full implications of the fact that He is man. As man, he is limited and finite, bound by time and space. He was really a zygote in his mother's womb, and only gradually developed his brain and bone and blood, and organs and systems, just as we do; and was born with an immature mind knowing only what a human baby knows, as Scripture says, "like us in all things but sin."
Do not expect to understand this quickly and effortlessly, because it is completely counter-intuitive and unparalleled in human experience. The Catechism says this:
"This human soul that the Son of God assumed is endowed with a true human knowledge. As such, this knowledge could not in itself be unlimited: it was exercised in the historical conditions of his existence in space and time. This is why the Son of God could, when he became man, "increase in wisdom and in stature, and in favor with God and man",and would even have to inquire for himself about what one in the human condition can learn only from experience. This corresponded to the reality of his voluntary emptying of himself, taking "the form of a slave".
(That whole section of the Catechism, which I've linked to, is very rich with knowledge and deserves a slow, careful reading.)
This is a mystery. This does not mean that we can't know anything about it, but that we can't know everything about it.
"For by his incarnation the Son of God has united Himself in some fashion with every man. He worked with human hands, he thought with a human mind, acted by human choice and loved with a human heart."
This can be found in a wonderful document of the Second Vatican Council, Gaudium et Spes ("Joy and Hope"), paragraph 22, about a fifth of the way down the page; once you click on the link, you can search the document using the phrase "with a human heart."
So yes: "He whom the whole universe cannot contain, was enclosed within the Virgin's womb, and became Man." And yes: the Omniscient had to learn to say "Ma-ma."