You can get a random number between 0 and 1 using the formula Random()
. If you add this into a table as a column formula and use Random(true)
, the value will update each time the row is edited. Depending on your scenario you could use this the Nth()
formula which returns the nth element in a list something of the form: List.Nth(Remainder(Random(true) * 1000, List.Count()).RoundDown() + 1)
Breaking this out:

Random(true) * 1000
will generate a random decimal number in the range 0 > 1000 
Remainder(Random(true) * 1000, List.Count()).RoundDown()
will convert this to a number in the range 0  N1 where the list is of length N 
List.Nth(Remainder(Random(true) * 1000, List.Count()).RoundDown() + 1)
will take that number returning the nth value in the list