Was there anyone in Japan a long time ago? How did an island country go to Japan? Who are the ancestors of Japan?

First of all, Japan is an island country now, not before. In the past, the north and south of Japan were connected with the mainland. Now the Sea of Japan is a lake. People immigrated to Japan from both sides. Archaeological findings show that ancient Japanese in the south and Ainu in the north have lived here at least in 10000 BC. The myths and legends of Japanese ancestors are Ye Yi Nagi and Ye Yi Nami, but the real ancestors are actually ancient Japanese, not what Xu Fu looks like. That myth is only a legend in China, and only some descendants of Han Chinese say so in Japan. Ironically, there are still so many people who believe that there is no archaeological discovery to prove that Xu Fu arrived in Japan, and judging from the navigation technology and climate at that time, even if Xu Fu really sailed eastward, he could only reach the Korean Peninsula. It is impossible to go to Japan by bypassing the Korean peninsula, and the evil Matai people in ancient Japan who came to China in the Han Dynasty never mentioned that people like Xu Fu had been to Japan. They heard that the Han Empire heard about it from people on the Korean Peninsula (another Korean nation, not the ancestors of present-day Korea and South Korea). In addition to the ancient Japanese, immigrants from Chinese mainland and the Korean Peninsula gradually integrated into Japanese society, and began to flood in in the Southern and Northern Dynasties. People go to Japan after every regime change. The more important person was the former Baekje royal family, and later he was integrated into the Japanese royal family, the ancestor of the famous Iga ninja clothing family. Modern genetic research shows that one third of Japanese genes are the same as those of China people, one third are the same as those of Korean people, and the other third are completely independent genetic samples. ...