16 years old, want to study in Japan. How can I get there without relatives and friends at home?

/kloc-you can't study in Japan before 0/8 years old, if your parents are not in Japan.

You can't go to a high school in Japan without a guardian (except the strange high school where you went to the third year of high school in Japan)

In Japan, there is no such thing as accompanying students, only families stay overnight or visit relatives. Students and students in language schools can't visit relatives in the office, and family organizations exist, generally referring to the spouses or children of foreign students. It is impossible for international students to do it without a fixed source of income.

The conclusion is that you can't go at present unless you 18 years old and come to Japan alone through a language school.