Tercüme - Brezilya Portekizcesi-Arapça - "Ilumina meu futuro. Suaviza meu destino".

I think it should be:
ينير مستقبلي و يجمل مصيري
or
ينير مستقبلي و يلطف مصيري
I prefer the first one though.

thank you for the advice,but I thought that "younirou"was a word for word interpretation that's why I've chosen " yaftahou abwaba mostahbali"
thanks a lot.

Well, there is a rule of thumb when you translate:
avoid too much wording!
sometimes, you just have to but it isn't the case here.
You've added a word that isn't mentioned in the actual text and I repeat that there was no real need for that!
A word for word translation isn't that bad.
At least not in all cases.
ينير مستقبلي
Is pure Arabic and none would argue, so why would we add more words for that?
no need.

thanks again for this piece of information