Your organisation is the workspace that holds your events, bookings, customers and settings. To ensure the basics are correct, head to Settings → Organisation to add the details specific to your organisation.
This is also where you set your organisation logo, contact details and social links - the logo you choose appears on your site and event pages.
The Notifications section controls your organiser alerts (new bookings and donations) and Attendee reminders - see Email notifications and what Bix sends.