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

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.

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

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.

This Case Forced Me to Completely Rethink How I Handle the Switch 2 - Gizmodo

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

Or

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

Can you believe the scumbag Harris had a microphone in her earrings? Slime is a synonym for Democrat.

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

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

You cannot effectively promote books

MAGA talking heads are saying that no MAGA child would publicly cry for their father, and want Gus Walz investigated as a crisis actor. I cried for my father and mother when they won or lost in life, am I a weird conservative or is MAGA messed up?

Or

C) that are unreadably terrible in any other way.

E) Take a solid year to learn how to use Amazon or Facebook ads and be prepared to lose quite a bit of money as you figure it out.

China Rare-Earth Magnet Maker Gets Green Light for US Exports - Bloomberg

Are you planning to proofread your book to avoid sentences such as

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.

A) that are not actually books.

Is it true that sleeping with your hair down can cause damage?

D) Pay promotion services like Written Word Media to promote your book. Legitimate services will not accept your book for promotion if the presentation is crappy or the book is badly written.