That might not be what you want - Number:Time represents a duration i.e. “90 minutes”, not a clock time of day.
Of you course you could use it to represent a time after midnight. Because it’s a single duration like “1,560 seconds” or “0.35 days”, it is tricky but not impossible to display and manipulate it in hours:minutes format.
You’ll find many “Alarm clock” examples on this forum that should give you a start.