Installation error message

Dear Support
I have tried to install airi pro but got the following error message:
Unpacking the package…

Installing the theme…

The package could not be installed. The theme is missing the style.css stylesheet.

Theme installation failed.

Hello, Airi Pro is a plugin, so please install it as a plugin.

You can check this documentation page for more information:

Please feel free to ask any other questions that you might have.

Kind Regards, Roman.