Explanation
COMPARTMENT A collection of related resources. Compartments are a fundamental component of Oracle Cloud Infrastructure for organizing and isolating your cloud resources. You use them to clearly separate resources for the purposes of measuring usage and billing, access (through the use of policies), and isolation (separating the resources for one project or business unit from another). A common approach is to create a compartment for each major part of your organization.
User Group can use some resources in the compartment like network resources also they can’t create it depend on the policy that assigned
Remember, a compartment is a logical grouping, not a physical one

Reference: https://developer.rackspace.com/blog/overview-of-IAM-in-oracle-cloud-infrastructure/
https://docs.oracle.com/en/cloud/paas/content-cloud/administer/create-instance-oracle-cloud- console.html#GUID-4855750C-F400-4FB4-85AA-96CC98FC5A06

Explanation
The Oracle Cloud Infrastructure Notifications service broadcasts messages to distributed components through a publish-subscribe pattern, delivering secure, highly reliable, low latency and durablemessages for applications hosted on Oracle Cloud Infrastructure and externally. Use Notifications to get notified when event rules are triggered or alarms are breached, or to directly publish a message.
Messages sent out as email by the Oracle Cloud Infrastructure Notifications service are processed and delivered through Oracle resources

Explanation
Components of IAMIAM uses the components described in this section. To better understand how the components fit together, see ExampleScenario.
RESOURCE
The cloud objects that your company’s employees create and use when interacting with Oracle Cloud Infrastructure. For example: compute instances, block storage volumes, virtual cloud networks (VCNs), subnets, route tables, etc.
USER
Anindividual employee or system that needs to manage or use your company’s Oracle Cloud Infrastructure resources. Users might need to launch instances, manage remote disks, work with your virtual cloud network, etc. End users of your application are not typically IAM users. Users have one or more IAM credentials (see User Credentials).
GROUP
A collection of users who all need the same type of access to a particular set of resources or compartment.
DYNAMIC GROUP
A special type of group that contains resources (such as compute instances) that match rules that you define (thus the membership can change dynamically as matching resources are created or deleted).These instances act as “principal” actors and can make API calls to services according to policies that you write for the dynamic group.
NETWORK SOURCE
A group of IP addresses that are allowed to access resources in your tenancy. The IP addresses can be public IP addresses or IP addresses from a VCN within your tenancy. After you create the network source, you use policy to restrict access to only requests that originate from the IPs in the network source.
COMPARTMENT
A collection of related resources. Compartments are a fundamental component of Oracle Cloud Infrastructure for organizing and isolating your cloud resources. You use them to clearly separate resources for the purposes of measuring usage and billing, access (through the use of policies), and isolation (separating the resources for one project or business unit from another). A common approach is to create a compartment for each major part of your organization. For more information, see Setting Up Your Tenancy.
TENANCY
The root compartment that contains all of your organization’s Oracle Cloud Infrastructure resources. Oracle automatically creates your company’s tenancy for you. Directly within thetenancy are your IAM entities (users, groups, compartments, and some policies; you can also put policies into compartments inside the tenancy). You place the other types of cloud resources (e.g., instances, virtual networks, block storage volumes, etc.) inside the compartments that you create.
POLICY
A document that specifies who can access which resources, and how. Access is granted at the group and compartment level, which means you can write a policy that gives a group a specific type of access within aspecific compartment, or to the tenancy itself. If you give a group access to the tenancy, the group automatically gets the same type of access to all the compartments inside the tenancy. For more information, see Example Scenario and How Policies Work. The word “policy” is used by people in different ways: to mean an individual statement written in the policy language; to mean a collection of statements in a single, named “policy” document (which has an Oracle Cloud ID (OCID) assigned to it); and to mean the overall body of policies your organization uses tocontrol access to resources.
HOME REGION
The region where your IAM resources reside. All IAM resources are global and available across all regions, but the master set of definitions reside in a single region, the home region. You must make changes to your IAM resources in your home region. The changes will be automatically propagated to all regions. For more information, see Managing Regions.
FEDERATION
A relationship that an administrator configures between an identity provider and a service provider. When you federate Oracle Cloud Infrastructure with an identity provider, you manage users and groups in the identity provider. You manage authorization in Oracle Cloud Infrastructure’s IAM service. Oracle Cloud Infrastructure tenancies are federated with Oracle Identity Cloud Service by default.
https://docs.cloud.oracle.com/en-us/iaas/Content/Identity/Concepts/overview.htm

Reference:
https://www.youtube.com/watch?v=XXqTGF8G0dk&list=PLKCk3OyNwIzuHYigVbdtDOZOfChcotfj2&inde x=6

Correct. Autonomous Database handles creating the database, and its maintenance tasks.

Reference: https://docs.oracle.com/en-
us/iaas/Content/Balance/Concepts/balanceoverview.htm#ariaid-title1

Resource Manager is an Oracle Cloud Infrastructure service that allows you to automate the process of provisioning your Oracle Cloud Infrastructure resources. Using Terraform, Resource Manager helps you install, configure, and manage resources through the “infrastructure-as-code” model. A Terraform configuration codifies your infrastructure in declarative configuration files. Resource Manager allows you to share and manage infrastructure configurations and state files across multiple teams and platforms. This infrastructure management can’t be done with local Terraform installations and Oracle Terraform modules alone. For more information about the Oracle Cloud Infrastructure Terraform provider, see Terraform Provider. For a general introduction to Terraform and the “infrastructure-as- code” model, see https://www.terraform.io. Reference: https://blogs.oracle.com/cloud- infrastructure/getting-started-with-the-resource-manager-on-oracle-cloud-infrastructure
https://www.terraform.io

Explanation
For highest level of resilience you can deploy the application between regions and distribute onavailability domain and fault domains.

Reference: https://www.oracle.com/assets/paas-iaas-pub-cld-srvs-pillar-4021422.pdf

Availability domains are isolated from each other, fault tolerant, and very unlikely to fail simultaneously or be impacted by the failure of another availability domain. When you configure your cloud services, use multiple availability domains to ensure high availability and to protect against resource failure.
Reference: https://docs.cloud.oracle.com/en-us/iaas/Content/GSG/Concepts/concepts.htm

Explanation
For more information onAlways Free Resources refer below official documentation page
https://docs.cloud.oracle.com/en-us/iaas/Content/FreeTier/resourceref.htm?Highlight=%20Always%20free OCI FastConnect is not offered as part of the Free tier:

Reference: https://docs.cloud.oracle.com/en-
us/iaas/Content/Billing/Concepts/usagereportsoverview.htm https://www.youtube.com/watch?v=- RGzG3F9G_s&list=PLKCk3OyNwIzuHYigVbdtDOZOfChcotfj2&index=10

Explanation
Oracle Compute Shape is coming with predefined or customize the number of OCPUs that are allocated to an instance. The amount of memory, network bandwidth, and number of VNICs scale proportionately with thenumber of OCPUs.