Control access to your reminders on Mac
Some apps and websites can use your reminders to provide you with services and features.
You can decide which apps are allowed to use your reminder information.
Choose Apple menu > System Settings, then click Privacy & Security in the sidebar. (You may need to scroll down.)
Click Reminders on the right.
Turn access to your reminders on or off for each app in the list.
If you allow third-party apps or websites to use your reminders information, any information they collect is governed by their terms and privacy policies. It’s recommended that you learn about the privacy practices of those parties.
If you’re a systems administrator and want information about deploying security settings, see Apple Platform Deployment.