This example doesn't specify a credential and a project intentionally. Terraform 0.13.0 or later is required.
$ gcloud auth application-default login
# export GOOGLE_PROJECT=terraform-toshi0607
# 【YOUR PROJECT】をあなたのGCPプロジェクトに置き換えてください。
$ export GOOGLE_PROJECT=【YOUR PROJECT】
$ terraform init
$ terraform plan
$ terraform apply
$ terraform destroy