BINGO is one of the permutations of the set of letters {"B","I","N","G","O"}, yes. As an example, another permutation of this set of letters would be "BGNIO" which does not spell an actual word. In fact, most of the permutations would not spell commonly used words.
If the probability of winning is 5/25, that can also be written as the decimal 0.2, yes. But the decimal value 0.20 is equal to 20% (must have the percent sign). "Percent" literally means "per 100" so 20% = 20/100 = 0.20.
