Install gnome-clocks by entering the following commands in the terminal:
sudo apt update sudo apt install gnome-clocks
Description:
Simple GNOME app with stopwatch, timer, and world clock support
GNOME Clocks is a simple application to show the time and date in multiple locations and set alarms or timers. A stopwatch is also included.
Homepage: https://wiki.gnome.org/Apps/Clocks
Version: 3.28.0-1
Section: universe/gnome