Becoming legally Japanese (the info site)

https://www.turning-japanese.info/2021/06/naturalization-sto...

Excerpt:

[...] the seven requirements [...]

    1) Have continuously lived in Japan for 5 years or more?

    2) Be 20 years of age or above, and be a legal adult in my home country?

    3) Be of upright conduct?

    4) Have a way of supporting myself and my family?

    5) Be willing to give up my other nationality/ies upon acquisition of Japanese nationality?

    6) Have never plotted to destroy the current government of Japan?

    7) Have a Japanese skill level enough to go about daily life, and be a functioning member of Japanese society? 

Note: Requirement 7 is not explicitly written in the Nationality Law of Japan, which has only 6 requirements. Nevertheless, as a prospective citizen, it is still a good idea to know the language, as it indirectly affects requirement 4 by affecting what kind of jobs you can take.