Not sure what exactly you're trying to do. Do want the user to (1) fill in time & date, or (2) do you want to pre-populate these fields, and/or (3) do these fields require validation?

All of the above is possible but require different configuration:

1. a simple single line of text field would do
2. you need to use the dynamic forms support (requires some PHP coding, see examples on the HELP! page)
3. providing regexps would allow user input validation, default values for these fields  to show the format, e.g. dd/mm/yyyy or hh:mm