According to the Nutanix Database Automation (NCP-DB) learning documents, to provision a new network in Clusters and extend it to Era, you need to:
B) Add the new subnet and VLAN in Network Configuration in PE1.
C）Add the new VLAN in Era Networks1.
These steps ensure that the new network is properly configured in both the Nutanix environment and Era, allowing for seamless communication and operation. Please refer to the official Nutanix documentation and training materials for more detailed information1.

In the Nutanix Database Automation (NCP-DB) framework, provisioning a new Oracle database through Era requires the configuration of both a Compute and a Storage profile1. The Compute profile is used to define the resources allocated to the database, such as CPU and memory, while the Storage profile is used to specify the storage configuration for the database. These profiles are essential in ensuring that the database is provisioned with the necessary resources and storage configurations for optimal performance23.

The Nutanix Era API documentation is available on the Nutanix.dev API Reference page12. This documentation outlines the operations that are possible with the Era APIs2. In addition to the API reference, the NutanixDev code samples repo provides working code that implements the practices shown in the documentation1. The Era API Explorer is another resource that provides a comprehensive view of the available APIs, allowing users to interactively explore and test the APIs. However, there is no mention of a specific "Era GitHub API Repository" or the "Nutanix Support Portal" being used as a reference resource for Nutanix Era APIs in the provided resources. Therefore, the correct answers are B： Nutanix.dev API Reference and C： Era API Explorer.