Explanation
You can use the Console or API to import exported images from Object Storage. To import an image, you need read access to the Object Storage object containing the image.
during the Import you can select the Launch mode:
For custom images where the image format is .oci, Oracle Cloud Infrastructure selects the applicable launch mode based on the launch mode for the source image.
For custom images exported from Oracle Cloud Infrastructure where the image type is QCOW2, select Native Mode.
To import other custom images select Paravirtualized Mode or Emulated Mode. For more information, see Bring Your Own Image (BYOI).

Explanation
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.
After creating a compartment, you need to write at least one policy for it, otherwise no one can access it (except administrators or users who have permissions set at the tenancy level). When creating a compartment inside another compartment, the compartment inherits access permissions from compartments higher up its hierarchy.
When you create an access policy, you need to specify which compartment to attach it to. This controls who can later modify or delete the policy. Depending on how you've designed your compartment hierarchy, you might attach it to the tenancy, a parent, or to the specific compartment itself.

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