Translation - Portugees-Engels - Eu vivo um dia de cada vez e o amanhã virá,...

It sounds weird to me. Wouldn'it be better something like:
I live one day at a time (or day by day) and tomorrow will come, wherever I may be?

Hi Apple, so the meaning is right, except the English is weird? (I've corrected it as per your suggestion.)

"Tomorrow" is a adverb and it should be written without article "the".
The article "the" is used before substantive ( masculine or feminine) only , so in this case, is just like Apple said it.