Increasingly I find myself writing about things beyond my experience. I was suspicious of trying but found that actually, it is possible when you embed yourself in imagination. I think if you can conjure a strong empathy for people and situation then you are capable of writing authentically. I also research details to add to the authenticity. A little bit of real detail goes a long way. I can read anything if the voice is authentic. Sometimes the story/experience may well be true but I disengage because the voice lacks a humanity and therefore falls short of real authenticity. But of course this is just personal taste.
You can also draw on similar experience or emotion to write about something you haven’t experienced. e.g. death of a parent to write about death of a friend. Experience is often on a sliding scale and no one is surely so fully removed from anything in this day and age of embedded journalism and an invasive media, that they can’t find a way to the truth of a subject without having been at the very crux of the experience.