You can change your data storage location, or load a different database folder in the Geneious Preferences under Tools→Preferences→General.
To move your database to a different location, either type the new location into the Data Storage Location filepath, or select the new location using the Browse button, click OK and at the prompt choose "move my documents to the new location".
To load a different database folder that already exists on your drive, click the "Browse" button next to Data Storage Location and navigate to the location of the database folder you wish to load.