Hey there harper610,
Thanks for reaching out to Apple Support Communities. I understand you’re having some issues editing and copying your photos on Mac. I’ll be happy to help.
Restart your Mac and go through the steps under ‘If you're having other issues with Photos’ from the following article first:
How to turn your Mac on or off
Get help with the Photos app on your Mac
After that, use the following links to guide you on exporting and editing your photos on your Mac and see if you continue to have issues:
Export photos, videos, and slideshows from Photos on Mac
How to edit photos on your Mac
If you still have issues after that, make sure all your software is up to date to further isolate this. Though this shouldn’t cause issues, it’s always a good idea to back up before updating:
How to back up your Mac
How to update the software on your Mac
Let me know if this helps.