On your Mac, choose Apple menu > System Settings, then click Apple Intelligence & Siri (or Siri ) in the sidebar. (You may need to scroll down.)
Open Siri settings for me
Click Siri Responses.
In the pop-up menu that appears, do any of the following:
Voice feedback: Turn off to mute Siri — the response from Siri is shown in the Siri window, but not spoken.
Always show requests: Turn on to show a transcription of your request on screen.
Always show Siri captions: Turn on to show what Siri says on screen.
Always show speech: Turn on to show what you say on screen.
You can also customise the apps Siri has access to. For more information, see Change Siri settings for accessibility on Mac