Hi there,
you could create a simple shortcode function like this:
function db_custom_field_shortcode() {
$custom_field = get_post_meta( get_the_ID(), 'your_custom_field_name', true );
$cf_content = '<p class="custom-class">' . $custom_field . '</p>';
return $cf_content;
}
add_shortcode( 'custom_field', 'db_custom_field_shortcode' );
Just change your_custom_field_name
to match your custom field.
And the [custom_field]
is the shortcode you add to your content.