Rusthunter I think all of those things work fine on GrapheneOS.
I think I've tried Google Calendar a while back for testing something and Pixel Camera works fine. I don't know about Google Lens, but I'd expect it'll work as expected.
Rusthunter what can I do to limit permissions while maintaining app functionality
On GrapheneOS, Google apps aren't privileged, so they have less access to your private data already. I'd say install the apps and just use them as you would normally use them. Pixel Camera will need camera and probably microphone access, so when it needs those permissions it'll ask for them.
If you want, you can use "only this time" when granting permissions. This means the app will not continue to have the permission for very long after you've finished using it.
You can also consider removing the network permission for some apps. One good example of that would be Pixel Camera. It doesn't need that permission for most of what it does. It may want to download some AI modeling stuff, so you can try launching Pixel Camera, play with some of the modes, then remove its network permission.