My American immigrant visa should have arrived, but I haven't received any documents and notices yet. How should we prepare and deal with it now?

If your appointment is coming soon, then your applicant in the United States should have received the relevant notice from the Immigration Bureau, and your file number will be on the notice. For example, in Guangdong province, the file number will start with GUZ. You can check this number on the website of the local consulate, or call. Generally speaking, if your address is correct and you haven't moved, the possibility of losing the interview notice is very small. Specifically, you can also ask Zhaolong immigrants, who know more about the process and details.