Simple counting..

[lsv]

How many alphabets need to be there in a language if one were to make 1 million distinct 3 digit initials using the alphabets of the language?

[tank]

I think the answer is 102

[Giscard]

100.

Assuming AAA/BBB is a distinct initial, if there is x alphabets in that language, then,

First digit = x way
Second digit = x way
Third digit = x way

Total x^3 way = 1,000,000
x = 100

[tank]

Oops! Had a typo. Thanks Giscard.