Split date/time to custom fields

Hello,
I am pretty newbie in WordPress and PHP, please could you give me an advice how to solve this issue?

I use date and time picker for event start/end. Then I use Elementor dynamic tags to display it. But I need to have two headings with different CSS format for day and for month.

My idea is to use save_post hook, separate these two figures picked in date/time picker and save them to another custom fields “day” and “month” as format e.g. “1” and “JAN”.

I tried code below (for month), but it is not working

add_action('save_post', 'separateEventStartDate', 10, 2);
function separateEventStartDate($post_id)
{
	// if date/time is not picked, return
	if (empty(get_post_meta($post_id, 'event_start', true))) {
		return;
	} else

	// load picked date and time to variable
	$eventStart = $_POST['pods_meta_event_start'];

	// change format to abbreviated month e.g. "JAN"
	$eventStartMonth = date("M", strtotime($eventStart));

	// save month to custom field
	update_post_meta($post_id, 'month', $eventStartMonth);
}

What am I asking:

1) Is it possible to make it this way?
2) What is the default format how PODS save date and time from picker. Is it object, array, string?
3) Do I use correct functions to get/save meta fields?
4) Is there a way to display (console, admin page) variable value to check it?

Thank you for any ideas!