If someone would go abroad in your hometown at age 12 then go back at age 33, I believe all people would still remember him as the son and brother of so and so..
Yes, people would still remember him. But they would not be amazed about where he got his knowledge because they would assume that he got it from wherever he came from.
But if he never left Galilee, then he suddenly displayed knowledge and miraculous powers, now that would be amazing.
What I am emphasizing is the similarities of the teachings of Confucius and Christ, Confucius ahead of Christ by 600 years.
Confucius was very different from Jesus.
Confucius preached his ideology of benevolence and righteousness that was based on loving people, but he did not go to the bottom level of the society to be friends with them. Jesus placed more importance on the poor, mingled with them, and made them his disciples.
Confucius said, “Gentlemen have nothing to compete for". Jesus not only competed with the Jewish religious leaders, he also ridiculed their interpretation of scripture while preaching his own doctrines.
Confucianism relied on the government, but Christianity emphasized spirituality over materialism.
Confucianism remained at the level of academic thought and self-cultivation. Christianity actively went out and preached the Gospel.
The "Golden Rule" did not start with Confucius. Statements that mirror the Golden Rule appeared as early as Ancient Egypt. Many prominent religious figures and philosophers have restated it in various ways. The author Rushworth Kidder notes that this framework appears prominently in many religions, including "Hinduism, Buddhism, Taoism, Zoroastrianism, and the rest of the world's major religions". The philosopher Simon Blackburn states that the Golden Rule can be "found in some form in almost every ethical tradition".
You say Confucius predates Jesus by 600 years. But in Judaism, the rule of loving your neighbor as yourself did not originate with Jesus, it originated with Moses. Thus, Leviticus 19:18 says: "
...love your neighbor as yourself".
The book of Leviticus was written sometime between 1440 and 1400 B.C., thus predating Confucius by 800 years.
In John 13:34, Jesus said: “
A new command I give you: Love one another. As I have loved you, so you must love one another.”
To love one another as Jesus loved us goes beyond the golden rule of loving your neighbor as yourself. Jesus emphasized this difference when he said it was "a NEW command", not the same command found in Leviticus.
That sort of teaching is definitely not Confucian.
And if Christ's early life is that of a normal child, then something must have happened to Him to learn such knowledge and wisdom.
Nothing happened to him. He always had that knowledge since the beginning of time because he is God incarnate.
John 1: 1-4; 14 says this about Jesus:
1In the beginning was the Word, and the Word was with God, and the Word was God.
2The same was in the beginning with God.
3All things were made by him; and without him was not any thing made that was made.
4In him was life; and the life was the light of men.
14And the Word was made flesh, and dwelt among us, (and we beheld his glory, the glory as of the only begotten of the Father,) full of grace and truth. God incarnate doesn't need to be taught by Confucius. That wouldn't make sense.
You say Jesus left for Tibet when he was 12 years old, then came back with knowledge at age 33 (should be age 30).
Don't forget that he already displayed great knowledge at 12 years old, when Mary and Joseph found him at the temple discussing with religious teachers:
46 After three days they found him in the temple courts, sitting among the teachers, listening to them and asking them questions. 47 Everyone who heard him was amazed at his understanding and his answers. 48 When his parents saw him, they were astonished. His mother said to him, “Son, why have you treated us like this? Your father and I have been anxiously searching for you.”
49 “Why were you searching for me?” he asked. “Didn’t you know I had to be in my Father’s house?” 50 But they did not understand what he was saying to them. (Luke 2:46-50) He didn't get that from Confucius, that's for sure. By your reckoning, he hadn't even left for abroad yet.