When you’re showing the page you will need to get that pages children.
https://codex.wordpress.org/Function_Reference/get_children
Then you’ll need to loop though those child pages in a secondary loop and show the fields from the child page.
ACF will only get fields from the current post id. If you know the ID values of each child page you can then get the field from the child page by including the pages id in the ACF function call.
$child_page_value = get_field('field_name', $child->ID);