The image shows an OCI Tenancy consisting of an OCI Region having an Availability Domain with an ebs-data-retention-compartment containing a VCN.

The VCN contains a:

Private Subnet A with a Windows VM and Linux VM connected by a bidirectional arrow.
Private Subnet B with Oracle APEX connected connected by a bidirectional arrow to OCI Identity and Access Management. Oracle Autonomous Data Warehouse (Shared) connected by a bidirectional arrow to the Linux VM, Buckets (database import using backups), unidirectional arrow to Backup/restore.
Private Subnet C with a Private Load Balancer connected by a bidirectional arrow to the Windows VM and connected by a bidirectional arrow to OCI Identity and Access Management.

On-premises consists of Customer data center, EBS production connected to OCI Region VCN via Service Gateway, Users CPE connected to OCI Region VCN via Site to Site VPN, DRG, and Admin users.