how to retrieve wordpress event manager plugin’s event detail using php? [closed]

Even this question is off-topic, you can use WordPress dedicated functions to retrieve all event custom fields and display them in your template or use it in your script.

You can have a look to WP_Query to retrieve events post-type and get_post_meta() for any custom field. Of course you can also use dedicated function create by the plugin, but it’s off-topic.

$args = array('post_type'=>'event', 'post_status'=>'publish', 'posts_per_page'=>-1);
$event_query = new WP_Query($args);

if ( $the_query->have_posts() ) {
echo '<ul>';
while ( $the_query->have_posts() ) {
    $the_query->the_post();
    echo get_post_meta($post->ID, 'event_start_date', true);
    echo get_post_meta($post->ID, 'event_end_date', true);
    echo '<li>' . get_the_title() . '</li>';
}
echo '</ul>';
/* Restore original Post Data */
wp_reset_postdata();
} else {
// no posts found
}

Hope it helps!