You can set timers to count down from specified times.
Siri: Say something like: “Set the timer for 3 minutes” or “Stop the timer.” on your iPhone.
next to a timer you’ve recently set.
Tap the timer to edit the label and sound.
When a timer ends, you get a notification at the top of your screen, no matter which app you’re using. Tap next to the timer to stop it momentarily. Tap Track time with the stopwatch in Clock on iPhone