If you are using ACF Plugin for adding custom fields in your WordPress website, and need to display those fields on your post detail page using hook, add this code in your WordPress website functions.php or add using Code Snippet plugin.
This function will display 4 Advanced Custom Fields Plugin (ACF) custom fields on the Post detail page. Custom fields are event_date, event_end_date, location, cost and website. Location will also show Google map of the location and embed on the post page. make sure to change these fields to match your own.
if your post type is different and not default ‘post’, make sure to change from is_singular(‘post’) to your post type.
Here is the full function code with hook on gist:
Hope that helps.