There were some great answers already. I would like to introduce an illustration which might help you as much as it has helped me to understand the distinction between the divinity and humanity of Christ.
God is spirit, Jesus Himself attests to this being true. John 4:24
Jesus says that He had glory prior to Creation John 17:5. Therefore He existed prior to Creation. This includes all the heavenly hosts, they come after day 1 (probably day 2). So right there He is attesting to being God and therefore a spirit because God is spirit.
The problem therefore is how does a spirit manifest itself and interact with the material realm? One possibility is to materialize or to take on a body (another is Spirit to spirit but that can bypass the faculties of the brain and mind and might not be all that beneficial materially speaking 1 Corinthians 14:14). That’s partly why Jesus became the visible God in the form of the Angel of the Lord and the Father was the invisible God. (This is referencing the two powers).
What I’m saying is that the (material) body is not the identity of the individual. The anatomy or the biological machine that houses the soul and spirit is not the sum total of who a person is. A person is more than mere chemical components. While we can interact with the physical part of a person through the senses, we can also interact with the non physical part like the mind, which is immaterial but entirely real.
We humans begin from the point of conception but not just the biological body but also our spirit is created. Our names might be in a registry called the Book of Life but we only start to exist after we are conceived. Our spirits are no stocked up in some warehouse waiting to be dispensed.
“The oracle of the word of the Lord concerning Israel: Thus declares the Lord, who stretched out the heavens and founded the earth and formed the spirit of man within him:”
The biggest difference with Jesus was that He IS and therefore the “He IS” (which is a spirit because He is God, and God is a spirit) is preexisting.
He didn’t need to be formed, He didn’t need a spirit to be formed, He just needed a body to inhabit.
The problem with the body is that it’s limiting. It’s very limiting. So it’s not that He lost His divinity, rather He chose to limit Himself voluntarily by taking on a limiting human body (non glorified body, non heavenly host-like or non ‘angel’-like body).
One limitation of the body is, you cannot be omnipresent.
Another is you cannot house all knowledge because even if all the knowledge is in the non physical mind or spirit, the processor or the brain cannot compute what it has not been taught. Jesus has to grow in knowledge while confined to a limiting body. Luke 2:52 (of course the glorified body has different properties 1 Corinthians 15:32)
So He relied on the Father to teach Him all things and was given the Spirit to do the things He saw the Father doing.
At any point He could have shed His body and escaped the “shell”. He had access to the Father to call legions of angels but He voluntarily showed restraint Matthew 26:53, He didn’t say He would call them Himself, rather He suppressed His omnipotency. He never stopped being God because the spirit that was in the biological machine was the second person of the Godhead Jesus, but He voluntarily chose not to access His divine attributes.
That’s simply all that Jesus was doing. He being a preexistent spirit took on a body. And that body had limitations right from the beginning. For one, it needed to grow and then be delivered via birth.
The reason some will argue that he stopped being divine might come from the fact that he chose voluntarily to suppress his divine attributes. He relied entirely on the Father and the Holy Spirit. He did not access his omnipresence, nor his omnipotency and nor his omniscience.
It also says that he took off his glory prior to even commencing the creation process. John 17:5 Meaning He stepped down voluntarily to take the role of the Angel of the Lord even before He started creating (some ~6950 years ago according to the Essene calendar)
So he appeared human, the thing that made him divine was that His Spirit was divine. Or put differently His Spirit was in fact God. Therefore God was inside a biological machine call a human body.
If nothing else this is encouraging to me, knowing that He was at no advantage and I’m at no disadvantage. If He could do it, then however He did it, I can too and He did it by not seeking His own will but only what the Father showed Him to do. Did nothing in His own strength but relied entirely on the strength of the Hole Spirit.