Dịch - Portuguese brazilian-English - também gosto de voces, desejo um bom dia e quem...

na minha opinião o sentido é percepivei mas talvez devesse ser escrito "...one day, we mait arrenge to have a lunch..."

I believe that "can" or "will" is necessary to guarantee clarity in this translation. (For English, anyway.)

"...we can/will arrange to have lunch someday."

Thanks Triton.
Just to keep the original tense in Portuguese I guess "will" fits better.