How to turn off Siri suggestions in Calendar?

Good afternoon mcsolaa,

Welcome to the Apple Support Communities!

I understand you would like to turn off Siri suggestions in Calendar. The resources below will explain how to do this on your Mac and on your iPhone.

Change Siri preferences on Mac - macOS User Guide

"On your Mac, use Siri preferences to choose a language and voice, turn voice feedback on or off, and manage which apps Siri can learn from and make suggestions. See Use Siri on your Mac.

To open Siri preferences, choose Apple menu  > System Preferences, then click Siri."

About Siri Suggestions on iPhone - iPhone User Guide

To turn off Siri Suggestions, go to Settings  > Siri & Search, then turn off any of the following:

• Suggestions in Search
• Suggestions in Lookup
• Suggestions on Lock Screen

For a specific app, tap the app, then turn off Show Siri Suggestions.

Happy Holidays!