I have two projects in Google Cloud and I need to copy files from an instance in one project to an instance in another project. I tried to using the \'gcloud compute copy-fi
One of the approaches to get permissions is to enable Cloud API access scopes. You may set them to Allow full access to all Cloud APIs.
Cloud API access scopes
Allow full access to all Cloud APIs
In console click on the instance and use EDIT button above. Scroll to the bottom and change Cloud API access scopes. See also this answer.
console
instance
EDIT