10. Autocomplete

One of the most complicated fields and requires a post_type array field - to suggest options for the user.

'autocom' => array(
    'type' => 'autocomplete',
    'post_type' => array('post'),
    'label' => esc_html__('Post to choose', 'masterstudy-lms-learning-management-system'),
),

But you can add your custom filter to suggested options - stm_wpcfto_autocomplete_autocom where autocom is a key of a field. You should pass an array of items like this:

add_filter('stm_wpcfto_autocomplete_autocom', function ($r, $args) {

    $r = array(
        array(
            'id' => 1,
            'title' => 'Title 1',
            'post_type' => '',
        ),
        array(
            'id' => 2,
            'title' => 'Title 2',
            'post_type' => '',
        ),
        array(
            'id' => 'fewfewbfhewvbfewjhvfewg',
            'title' => 'Title 3 with rand -' . rand(),
            'post_type' => '',
        ),
        array(
            'id' => 4,
            'title' => 'Title 4 with rand -' . rand(),
            'post_type' => '',
        ),
    );

    return $r;

}, 10, 2);

If you need to limit added options you can add "limit" parameter to field

'limit' => 1