Oracle Cloud Infrastructure File Storage service provides a durable, scalable, secure, enterprise-grade network file system. You can connect to a File Storage service file system from any bare metal, virtual machine, or container instance in your Virtual Cloud Network (VCN). You can also access a file system from outside the VCN using Oracle Cloud Infrastructure FastConnect and Internet Protocol security (IPSec) virtual private network (VPN).
Large Compute clusters of thousands of instances can use the File Storage service for high-performance shared storage. Storage provisioning is fully managed and automatic as your use scales from a single byte to exabytes without upfront provisioning.
Reference:
https://docs.cloud.oracle.com/en-us/iaas/Content/File/Concepts/filestorageoverview.htm

Explanation
A shape is a template that determines the number of CPUs, amount of memory, and other resources that are allocated to an instance.
Standard shapes don't incur costs in a STOPPED state.

When creating a compartment, you must provide a name for it (maximum 100 characters, including letters, numbers, periods, hyphens, and underscores) that is unique within its parent compartment. You must also provide a description, which is a non-unique, changeable description for the compartment, from 1 through 400 characters. Oracle will also assign the compartment a unique ID called an Oracle Cloud ID.
You can create subcompartments in compartments to create hierarchies that are six levels deep.
Reference:
https://docs.cloud.oracle.com/en-us/iaas/Content/Identity/Tasks/managingcompartments.htm When you first start working with Oracle Cloud Infrastructure, you need to think carefully about how you want to use compartments to organize and isolate your cloud resources. Compartments are fundamental to that process. Most resources can be moved between compartments. However, it's important to think through your compartment design for your organization up front, before implementing anything. For more information, see Setting Up Your Tenancy.
The Console is designed to display your resources by compartment within the current region. When you work with your resources in the Console, you must choose which compartment to work in from a list on the page. That list is filtered to show only the compartments in the tenancy that you have permission to access. If you're an administrator, you'll have permission to view all compartments and work with any compartment's resources, but if you're a user with limited access, you probably won't.
Compartments are tenancy-wide, across regions. When you create a compartment, it is available in every region that your tenancy is subscribed to. You can get a cross-region view of your resources in a specific compartment with the compartment explorer. See Viewing All Resources in a Compartment.
You can create subcompartments in compartments to create hierarchies that are six levels deep.

To design a high availability architecture, three key elements should be considered- redundancy, monitoring, and failover:
1) Redundancy means that multiple components can perform the same task. The problem of a single point of failure is eliminated because redundant components can take over a task performed by a component that has failed.
2) Monitoring means checking whether or not a component is working properly.
3) Failover is the process by which a secondary component becomes primary when the primary component fails.
The best practices introduced here focus on these three key elements. Although high availability can be achieved at many different levels, including the application level and the cloud infrastructure level, here we will focus on the cloud infrastructure level.
An Oracle Cloud Infrastructure region is a localized geographic area composed of one or more availability domains, each composed of three fault domains. High availability is ensured by a redundancy of fault domains within the availability domains.
An availability domain is one or more data centers located within a region. Availability domains are isolated from each other, fault tolerant, and unlikely to fail simultaneously. Because availability domains do not share physical infrastructure, such as power or cooling, or the internal availability domain network, a failure that impacts one availability domain is unlikely to impact the availability of others.
A fault domain is a grouping of hardware and infrastructure within an availability domain. Each availability domain contains three fault domains. Fault domains let you distribute your instances so that they are not on the same physical hardware within a single availability domain. As a result, an unexpected hardware failure or a Compute hardware maintenance that affects one fault domain does not affect instances in other fault domains. You can optionally specify the fault domain for a new instance at launch time, or you can let the system select one for you.
All the availability domains in a region are connected to each other by a low-latency, high bandwidth network. This predictable, encrypted interconnection between availability domains provides the building blocks for both high availability and disaster recovery.