Use function wp_get_schedules() to see all scheduled events. See https://maheshwaghmare.com/doc/wordpress-cron/

get-schedules.php

<?php
print_r( wp_get_schedules() );

// Array
// (
//     [hourly] => Array
//         (
//             [interval] => 3600
//             [display] => Once Hourly
//         )

//     [twicedaily] => Array
//         (
//             [interval] => 43200
//             [display] => Twice Daily
//         )

//     [daily] => Array
//         (
//             [interval] => 86400
//             [display] => Once Daily
//         )

//     [weekly] => Array
//         (
//             [interval] => 604800
//             [display] => Once Weekly
//         )

// )