Time Fields store values that represent a specified hour and minute of a day. Depending on how your app's time format settings are configured, the value will store AM/PM period will also be stored appropriately.
Below, you can find an example of a Time Field in a form with the Default Form Value set to 12:00 PM. In this example, you can observe our time selector for forms and how the Default Form Value resets the value upon form submission.
If you would like your Date Fields to appear in a different format, you may do this in the Layout & Format Settings in your app Settings.