Probability of sequences can be calculated by multiplying the probability of the first event by the probability of the second, and so on.
The number of events we have in this situation is 2, one for each die. Each die has a 1/6 chance of landing a six, and we need two to win. So, the probability of this event is 1/6 times 1/6, or 1/36.
Alana has a 1/36 chance of winning by rolling two sixes.