How does a new KDP writer supposed to market a book?

C) Persuade book reviewers on BookTok or Substack or someplace to recommend your book. If your book is unreadably terrible, this is probably impossible.

B) that are filled to the brim with typos or errors.

If your book is well presented, well written, and basically free of typos, then

What's the most incredible coincidence that ever happened to you?

Because you cannot persuade readers to buy any book in which sentences do not make sense. This shouldn't be “does.” If you don't see the problem, that is a big problem.

B) Build a newsletter mailing list of people who will buy your book because they trust you to write books they want to read. This is slow, but ideal.

D) that are presented with bad covers, bad descriptions, or ludicrously bad interior formatting.

What are some photos of masturbation?

A) Build a following on social media, a following of people who will buy your books. Good luck with that. There is very little evidence that social media can translate to sales.