Salam Paul
It is generally a Hindu concept that God can become a human being. They say that God is so holy, so pure, He cannot understand the shortcomings of human beings. Since God is pure, He does not understand pure, sadness, happiness. So God requires to be a human being so that He can understand human beings and understand what is good or bad for human beings. But a simple reply to this concept is that if I make a computer, do I have to become a computer to know what is good or bad for a computer. No, since I am the creator of that computer, I already know what is good/bad for the computer. I instead write an instruction manual for that computer, so people know how to use that computer. Same is our case, God has not come down from heavens as a human being, instead God has written an instruction manual for us. We call it Quran.
But Christians give another argument. They say that mankind is born in sin because of what Adam and Eve did in heaven. They sinned so now all of us bear the burden of sin. Therefore we require God to come down, crucify himself on the cross and sacrifice himself in order to relieve us from the bondage of sin. First of all, I want to ask you, did Adam ask any of us before eating the apple. Did he ask for our opinion? No, so how can we be blamed?
Even the Bible says
"The soul that sinneth, it shall die. The son shall not bear the iniquity of the father, neither shall the father bear the iniquity of the son; the righteousness of the righteous shall be upon him and the wickedness of the wicked shall be upon him. “But if the wicked will turn from all his sins that he hath committed, and keep all my statuses and do that which is lawful and right, he shall surely live, he shall not die. All his transgressions that he hath committed, they shall not be mentioned unto him; in his righteousness that he hath done, he shall live.” Ezekiel 18:20-22
Hence since we are not to blame, we do not require God to come down and sacrifice himself.
Furthermore, if you analyse, God and human beings are pretty opposite. God does not require to eat, we do. How can we have a person who requires to eat and does not require to eat at the same time. Same can be said about sleeping, drinking etc.