何だっていい
Meanings
1
anything is fine; it doesn't matter what
Colloquial expression used when the speaker is indifferent to the choice or outcome. Often implies a relaxed or slightly dismissive attitude. Compare with 何でもいい, which is more neutral.
See also: 何でもいい
Anything is fine for lunch.
It doesn't matter what the result is. The important thing is to try.