How to edit blog page in wordpress? there is no place to put shortcode

I doubt most of the WordPress themes have the in-built functionality you’re needing.

You will have to check out your theme’s single.php file and find out if it’s including a sidebar template (it should), check that template and make sure it has the necessary action/hook to programmatically insert custom elements into your blog and blog posts sidebar.

Several themes actually have both before_ and after_ sidebar actions, but i can’t guarantee yours has it (if not, you’ll probably have to create a child theme or a custom plugin to begin with).

After you’ve managed to determine the correct action to be used, you’ll have to add some code (into functions.php – probably a child theme’s – or a custom plugin) to output your custom field’s value.

In example, if your theme provides an action called my_theme_before_sidebar_items, you’ll see something like this:

do_action( 'my_theme_before_sidebar_items' );

And you’ll be able to use the above action this way:

add_action( 'my_theme_before_sidebar_items', 'my_custom_function' );
function my_custom_function() {
    // This will handle blog posts' sidebar. You might need a different approach to handle your blog's sidebar
    global $post;
    echo do_shortcode( get_field( 'my_custom_field', $post->ID ) );
}

Of course, the above my_custom_field is the example reference name for your ACF field.

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