Buy this book now.
On the How To Be a Grownup bookshelf every person should have, there should be at least three titles: something on how to cook some basic food, something on personal finance, and Sana Goldberg's How To Be a Patient.
This book literally covers all the things that most people don't know, or that they only know if they've got a smart doctor (or three) in the family or if they were raised by a parent who REALLY knew their stuff. I'm in the latter category, and I've had my fair share of dealing with the medical establishment for acute and chronic conditions, so I would say this is the book I would have asked to have been written.
Goldberg covers everything, in appropriate (but not confusing) detail: how to be your own health advocate, how to select primary care and other health care providers, how to prepare your own medical records and documentation (like advanced care directives), the basics of pharmacology, how to get better care from a biased system, how to talk to healthcare providers to be heard, how to navigate screenings, vaccines, chronic and emergency care, how to prepare for a procedure or hospital experience...and more!
Written for the patient, but with care advice for partners, families, and friends, this book manages, in one volume, to provide more essential advice than I've ever seen in one place, and does it well. There's even a section for handling insurance and financial issues, and appendices on everything from vaccine schedules to the types of free screenings available under the ACA.
Finally, Goldberg gets extra points for acknowledging the need for special guidance for healthcare issues when the patient is not a straight white mail (in other words -- most of the time). From pain and the gender gap to gender differences in the presentation of heart attacks, to LGBTQ issues, to how implicit bias and systemic oppression can stymie the patient experience (to the point of endangering lives) and how to counteract that bias and oppression.
Get this book, read it, put tape flags or bookmarks at the sections to which you know you'll need to return again and again. If I could give this more than 5 stars, I would!