Civil partnership is also known as the civil union between 2 individuals. It is a legally acknowledged partnership where partners of the same-sex or the opposite-sex register themselves under the UK law. You can also initiate British citizenship application once you have lived for a minimum of 3 years in civil partnership. Eligibility includes a minimum age of 16 years, if you are below 18 and above 16 years, parents consent is a must, neither of you should be married. Planning and notice giving should be done before 29 days of ceremony. Read here full article: The Best Guide for Civil Partnerships in the UK