Can I apply for immigration after working in Japan for three years?

Theoretically, it can be renewed for another two years. Immigration requires paying taxes for eight to ten years. In other words, you have to work in Japan for eight to ten years. In Japan this is called planning, which means changing nationality. Then there is the resident visa, which is the Japanese green card. It is impossible for technical intern trainees to achieve the above in three years. You can apply for a study abroad or investment visa when the time comes. Japanese citizenship is easier to obtain than a Japanese green card.