Do I know what the Christ is?
He became human, but He also never gave up His diety completely, so I would hazard a guess that I have a better understanding of what the Christ is than you give me credit for. If He wasn’t a “human person” then He couldn’t qualify as an atoning sacrifice for our sins.
He is fully God and fully Man at the same time.
Yes ... but He is one person, not two, and that Person is Divine. Because He is a Divine Person, His sacrifice is perfect ... therefore His sacrifice, carried out in His human nature, could atone for our sins.