I’ve been working on a draft in Word. Can I import it into Scrivener and have it automatically (or with prompts) split my work into chapters/scenes which I can then analyse for plotting purposes?
Welcome to the Scrivener world and this forum!
In answer to your question, yes.
Full instructions with no need to repeat here are in section 9.1.6 in the Scrivener Manual.
While there, scan the huge document to be come aware of what’s there in case needed in future. For sure, if not done already, go through the Scrivener Tutorial (on Help Menu) and see the FAQ’s on L&L’s web site. You might also get value from purchasing one of the many fine books on Scrivener that L&L lists on their web site.
Check if your Word document has chapter headers or scene headers with an “Outline Level” in the Style’s paragraph setting. Scrivener can use these to Import and Split the doc with the nested structure of the document intact.