Hello Volkswriter,
Thanks for reaching out to the Apple Support Communities! We understand you are encountering some issues with using Zoom on your new Mac and not being able to screen share. We are happy to help provide some guidance.
To begin, we would recommend restarting the Mac if you haven't already and try to use screen sharing in Zoom again. If that doesn't work and the issue persists, we have some other great steps to go over listed in this helpful article:
If an app on your Mac stops responding, closes unexpectedly, or won’t open
It covers some good steps to try in regards to updating or reinstalling the app, and even how to contact the app developer if the issue persists.
We want to make sure we cover all bases that we can here, so we'd like to ask some additional questions to get a better understanding of whats happening.
- What happens when you try screen sharing in Zoom? Do you get any error messages? If so, what does the error message say?
- Are you experiencing any issues with using other apps that use video, such as FaceTime?
Keep us updated on how it goes and the answers to those questions. We hope this information helps.
Best Regards.