How to show “Related post” in post detail screen?

Screenshots

To show this content must go to Post Detail of App Builder to set:

Note:
Query by “Custom field” check below

When set Query by “Custom field”, we should install 2 plugins

Note

You must setting Request Version of ACF to REST API in Permalink => Setting => Dashboard is V3

Create a field in Custom Fields

And, we can create or edit a post on dashboard to use this field.