Immigration to Italy (family reunion). My mother is over there and immigrated me through family reunion. How long can I stay there? Introduce it in detail

As long as you are effective, you can stay. Generally, the first stay is valid for 2 years, and then you will continue to stay. You can get permanent residence with a validity of 0 after registering your ID card with the Italian government for five years, but you have to take the Italian exam held by the government every year.