How can I acquire British citizenship if my father is a British citizen? He resides in England, but I was born in the Caribbean in 1981. My parents were not married. Could you provide me with the process of acquiring citizenship?
You are eligible for British Citizenship , provided your father was a British citizen 'other than by descent' (usually this means he was born in the UK). It makes no difference that your parents were not married (thanks to the Immigration Act of 2014 which explicitly grants eligibility to those who would have been eligible if their parents had been married)
This website gives the application procedure.
This gives more technical information about the requirements for British citizenship.