best translation
 

ok i have to explain to my girl friend the meaning of

"What will be will be." what is that in Japanese?

and what is なんとかなれ、なんとかなる。（I think it means ”it will all be ok”)


please help

The song "que sera sera" (Whatever will be will be) is in Wikipedia. The Japanese page translates the title as "なるようになる."
ケセラセラ - Wikipedia

If I were to take the thread title literally, then KyleGoetz has given you the answer. The other one that's used just as frequently or even more so is なるようにしかならない.

Grammatically, however, these Japanese phrases have nothing to do with "What will be will be." If you want the person to really "undetstand" this English phrase, a full grammar explanation might be in order instead of just giving the "translation", in which none of the three words (what, will, be) are used.

maybe:

そのうちに分かる?
見ると分かる?
slightly different meaning, but ends on the same :P

Huh? Do you speak Japanese (or English for that matter)?

Those have very different "feelings" from "What will be will be".

Yeah, those don't mean anything like the English phrase "whatever will be will be."

The English phrase basically means "life throws crap at you, and you should just accept whatever happens, because you can't stop it." To quote Wikipedia,That second one you suggested just means "When you see it, you understand." The use of と there implies that it is a natural effect of seeing it that you will understand it, by the way.