Your event module is pre-configured to accept reservations, even to take payments from your visitors who book through your site! Attendees who book through your site must submit payment via PayPal, so if you don’t yet have a PayPal account you will need to establish one and enter the email address associated with your PayPal account under ‘Events’ / ‘Settings’ in your admin navigation menu.
The payment module is strictly optional – if you don’t want to charge for the events you list and promote on your site, you don’t need to set a price for RSVPing.