Yes kiosk or online
You can buy at the kiosk, or if it's brand new and busy buy on line.
If you want but you don't have to do it, but it's recommended
You can, but 100% of the time they will be available. Just make sure you go a little early. If it is the first showing of a movie I would definitely arrive 1 hour early. You can reserve tickets online as well. I would only call, if you are running late.
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