How to get year, month and hour in WordPress?

PHP Date Format in WordPress function:

You’ll have to use the proper date format string (as used in PHP date function) in the WordPress get_the_date() function’s first parameter.

For example, to get the Date & Time in the format like 2018-07-23 23:59 (i.e. YYYY-MM-DD HH:MM, where hour is in 24 hour format), you need CODE like:

get_the_date('Y-m-d H:i');

Or, to get the Date & Time in the format like 23-07-2018 11:59 PM (i.e. YYYY-MM-DD HH:MM AM/PM, where hour is in 12 hour format with AM or PM), you need CODE like:

get_the_date('d-m-Y h:i A');

So your full example CODE will be:

print '<time class="entry-date updated" datetime="' . esc_attr( get_the_date( 'c' ) ) . '">' . esc_html( get_the_date( 'd-m-Y h:i A' ) )  .  '</time>';

Mistakes in your CODE:

The idea in your CODE is not entirely wrong, only the CODE has two mistakes:

1. You’ve used the the_date function, instead of get_the_date function. The way you’ve concatenated the string, the_date will not work as it prints the date immediately, doesn’t return as the get_the_date function does.

2. You’ve used 'F j, Y', 'G:i' as two parameters, where as, it should be just one parameter: 'F j, Y G:i'.

So if you correct these two mistakes, the proper CODE will be:

print '<time class="entry-date updated" datetime="' . esc_attr( get_the_date( 'c' ) ) . '">' . esc_html( get_the_date( 'F j, Y G:i' ) )  .  '</time>';

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Further Reading:

There are many other possibilities and all are in the Date Format string as described in PHP date function documentation. There are some useful examples in WordPress Codex as well.