question regarding to letting screen reader user turn chapters

Hi folks

Which way will screen reader users prefer for a reading system to move to
next or prev chapter?

The website wysebee.com added more a11y support recently. So it is supposed
to help screen reader users easily reach an accessible book. (one of the
most important mission of wysebee.com is to have accessibility support as
first priority and a11y friendly content as first class citizen)

Now I have an issue to solve - how to move to the next and previous chapter
easily (with less steps). I am using both Mac voice over and Android
Talkback to test at this moment.

The first accessible book I put in the website is the Accessible EPUB 3 and
when I close my eyes and open that book I wonder how I can turn to next
chapters (Wysebee is trying no pagination but scroll or turn chapter
approach.). So right now Wysebee.com just show the first chapter at this
moment. I am thinking about two ways - A. simply add next/prev chapter
outside of the chapter frame or B. embed next/prev chapter button to end of
each chapter xhtml. And I don't know which one would be better.
Do ppl usually go outside from frame and trying to find the turn chapter
button? Or should I embed something in chapter html so that the end user
does not need to use a voiceover command to move out of frame to find a way
to change chapter?

Which way will screen reader users prefer from a reader perspective?

Cheers,
Zheng