Create an IBM Cloud service ID, then create and download an API key for that service ID

main.tf

# See https://cloud.ibm.com/docs/terraform?topic=terraform-getting-started
# for details on IBM Cloud and Terraform

# First, obtain an IBM Cloud IAM token
# Thereafter, create a new IAM service ID and as
# follow-up step, using a local execution environment,
# utilize curl to create and download an API key.

# Obtain the IBM Cloud IAM authentication token
# It is needed for the embedded curl command below
data "ibm_iam_auth_token" "iam_tokendata" {}

# Create a service ID
resource "ibm_iam_service_id" "myServiceID" {
  name        = "myServiceID"
  description = "ServiceID for demonstrating API key access"

  # create and download API key
  provisioner "local-exec" {
    command = "curl -X POST 'https://iam.cloud.ibm.com/v1/apikeys' -H 'Authorization: ${data.ibm_iam_auth_token.iam_tokendata.iam_access_token}' -H 'Content-Type: application/json' -d '{ \"name\":\"myServiceID-key\", \"iam_id\":\"iam-${ibm_iam_service_id.myServiceID.id}\", \"store_value\": true}' > myServiceID-key.json"
  }
}

See https://stackoverflow.com/questions/63557050/ibm-cloud-and-terraform-how-to-create-and-download-api-key