How to apply for a British relative immigrant visa

The applicant's spouse and children under the age of 18 can apply for going to the UK as family members, but before going to the UK, they need to apply for an entry visa from embassies and consulates in China, UK on the grounds of accompanying family members. In addition, the applicant must prove that he has enough ability to pay all the living expenses of his family after going to Britain. The applicant's parents are not included in the accompanying family members. After the applicant has obtained the British permanent residency or British nationality, he can apply for parents' reunion immigration, but the following conditions must be met: 1) The guarantor (child) of the applicant has obtained the British nationality/permanent residency; 2) One or both parents are over 65 years old; 3) Parents are in poor health and need long-term care; 4) No other immediate family members, caregivers or domestic workers provide care in China; 5) Parents have no old-age security in China, or the pension is not enough to support daily living expenses; 6) When living in China, all or most of the living expenses come from the applicant's guarantor (children) in the UK; 7) The applicant's guarantor (children) can provide accommodation for parents and bear the living expenses without seeking public funds.