Autobiography vs Memoir
Should I write an autobiography or a memoir?
It depends on you. Technically, an autobiography is the story of your life until now. A memoir is a particular part of your life, perhaps an event in which you were involved, a goal you achieved, a problem you solved.
As a rule, a memoir has a start and a finish … and a point.
It's whatever that point is that will make your memoir of interest to other people, especially if your story might help people going through what you went through. Or even if it's just entertaining.
Autobiographies tend to be far larger, more sprawling, and without such a clear focus as memoirs – depending on the story of your life, of course, or the scale of your ambition.
For most authors, a memoir is the probably a better choice.
And it avoids having to wait until you've lived long enough to feel that you can justify writing an autobiography.