For the App Store to work you need A) Internet connection, b) An Apple account, c) Payment card to buy apps.
Also, I would consider deleting any old preferences/settings for the App Store from your ~\Library\Preferences and possibly Application Support folders which may cause a malfunctioning app.
Also, I would consider deleting any old preferences/settings for the App Store from your ~\Library\Preferences and possibly Application Support folders which may cause a malfunctioning app.