The short answer to this is: you will not know until you try. We assume that writers are the ones who have a drive to write and will turn up at the desk no matter what.
This doesn’t mean that turning up is always easy. Procrastination can be self-doubt in sheep’s clothing. So can the sense that one does not yet have enough material to begin. But ultimately, the only way to know whether you do or don’t have enough material is to start writing.