When and how to get a visa after receiving the letter from the Immigration Bureau approving my sister's application for immigration?

First of all, I will definitely answer you; This letter only writes the name of the main applicant, and it is not on the same list. Your final refusal will not affect it, because your situation is that the applicant has a thick financial guarantee; Right? The interview must be in Guangzhou, which cannot be changed. The whole family will go to see the official, not answer in English, and there will be assistants to help. You should prepare relevant materials after waiting for a letter or phone call, preferably.