What tickets should I buy if I want to see the final performances for Nationals?

Hi, I have no idea how the event works, and I wanted to surprise my wife with tickets to Nationals. I want her to be able to see the final performances to determine the winners, but I don’t know what I’m doing. Do I get the Free Dance or the Short program? Or are they different things? Do they add the scores of those two events together? Any help is appreciated!