Have your Mac speak announcements
You can have your Mac speak the text in dialogs and other announcements and notify you when an app needs you to perform an action.
On your Mac, choose Apple menu > System Settings, then click Accessibility in the sidebar. (You may need to scroll down.)
Click Spoken Content on the right.
Turn on “Speak announcements,” click the Info button , then set any of the following options:
Voice: Choose a voice to speak the announcements. To select and download additional voices, click the pop-up menu, then choose Manage Voices.
Phrase: Choose the phrase you want to hear before the text of the announcement (the name of the app associated with the announcement is included). To add your own phrase, click the pop-up menu, then choose Edit Phrase List.
Delay: Drag the slider to set the number of seconds you want your Mac to wait before it speaks.
To hear a preview of your selections, click Play Sample.
When you’re done setting options, click OK.
You can also use VoiceOver, the built-in screen reader for macOS, to hear descriptions of items on the screen and to control your Mac using the keyboard. See the VoiceOver User Guide.