As I pointed in the title. What is the correct answer to 国籍. Is it, for example, Japanese or Japan. I am confused because I found contradictory translations when I tried to look on the internet. Thank you.
国籍 means "country", so we say 日本国籍, not 日本人国籍. To have 日本国籍 means "to be Japanese".
国籍 means nationality and it implies that the one who has the 国籍 has a formal document for it. (籍 originally means "document" e.g. 戸籍)
I think a translation like "the country of citizenship" is used in a sentence like 国籍は日本です
According to 国籍法 Japanese Nationality Act, 国籍 refers to Japanese Nationality.
Here is 国籍法 Japanese Nationality Act. http://www.moj.go.jp/MINJI/kokusekiho.html
（この法律の目的） (Purpose of This Act)
Article 1 The requirements of Japanese citizenship shall be governed by the provisions of this Act.
English translation of Japanese Nationality Act