Here’s how to download/upload files using gcloud compute scp.

Make sure you are authenticated.

gcloud auth login

How to download.

gcloud compute scp --recurse your-server:/home/username/yaml.tar.gz . \
--project your-project-id \
--zone us-central1-a \
--internal-ip

How to upload.

gcloud compute scp --recurse yaml.tar.gz your-server:/home/username/ \
--project your-project-id \
--zone us-central1-a \
--internal-ip