Mac os installation

Moses- Said:

"Mac os installation: I mistakenly formatted my hard drive , what can i do to reinstall the Mac os, this is what it's displaying at the moment"

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Visit this link: If your Mac Starts Up to a Question Mark - Apple Support

Boot into Recovery Mode.

Recovery provides the equivalent environment of the release DVDs -- Utilities available and the ability to download and Install macOS.

How to reinstall macOS - Apple Support

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