Hi Andrew!
Thanks for reaching out. I will try to help with your questions.
To be able to sell tickets to the events, you would need the free Event Tickets plugin, and the Premium Event Tickets Plus plugin.
When the tickets plugins are used in conjunction with The Events Calendar, the form for tickets is on the single event page. Users need to visit each event to add tickets to the cart. Once on the event page, when adding the tickets, the user is brought to the checkout page. They can go back to the calendar and add more tickets to the cart, but each time they are brought to the cart when adding them.
In order to provide discounts, you would need to find a third party plugin that works with your ecommerce plugin, WooCommerce for example. There are several WooCommerce discount plugins out there, you can Google to find which best your needs.
Hope this helps! Please let us know if you have any further questions.
Thanks,
Sky