Is buying a house in Argentina an immigration?

Not immigrants. You can immigrate if you buy a house. With China's cleverness, everyone has gained identity through this move. Moreover, in most European countries, unless one parent must have the nationality, the nationality of landing is not implemented. In China and Argentina, most people hold residence permits, so after the baby is born, they all hold China passports.

You have a misunderstanding about immigration. The vast majority of immigrants hold residence permits or green cards, that is, temporary residence permits.

If you want to become a citizen, you must live in that country for at least a few years, and then you must pass the exam to obtain citizenship.