Go to the library and borrow a book or two on family research. Ancestry and other sites have tutorials.

When you research, start with yourself and work backward. If you don't know the details of your parents' marriage and births, obtain certificates. You probably know your mother's maiden name. Find her parents' details. Find your father's parents details. And so on, and so on. Some of this will be hard work. Only some information is available online. Be prepared to research in libraries and county offices, and realize that to do a good job at it means obtaining bmd certificates, which cost money. This is not a cheap hobby.

HH