How to send email/SMS based on dynamic date & time?

I have schedule date & time field in one doctype.
When I create any new doctype then I want to send an email/SMS automatically based on date & time is added in schedule date & time field. So how to do that ?
Also after email/SMS is sent on that date & time then it should not send next day again.

@shruti_prajapati use Notification .

Thanks for the solution.
At what time it will send an email ?
Because I have datetime field so I need to send an email at that particular date & time.

@shruti_prajapati it will send it at the same date but not at the same time probably at midnight