Click on the Clock tab. Here, you have a variety of options to choose from.
You can opt to show the date and time in the menu bar. You can also have the time show seconds, use flashing separators, and more.
Check the box for Announce the Time, and your Mac will say the time on the hour, half, hour, or quarter hour. Click Customize Voice to choose a voice, adjust the volume, and more.
When you’re done, click on the close window button (the X button on the upper left), or press command-Q on your keyboard.