How do I display a date correctly that is stored in the database as a backwards 8 digit number from Advanced Custom Fields? [closed]

Question

I voted to close your question, because it is pretty much a PHP problem, not a WordPress one and thus off topic on here. Nonetheless here comes some help.

General information about

Formatting Date and Time

from the WordPress codex you might find helpful.

Aside from that, on the PHP side of things, the date function and the datetime class are pretty much what you are after. There are a lot of other things, but those two will give you a good starting point.

One example based on DateTime::createFromFormat to follow up on:

$date = DateTime::createFromFormat( 'Ymd', '20140508' );
echo $date->format('d/m/Y');

Good luck going from here!