The words "que sera, sera" in the song of the same name may be Spanish but the phrase makes no sense. According to Wikipedia,
Composer Jay Livingston had seen the 1954 film The Barefoot Contessa, in which an Italian family has the motto "Che sarà sarà" carved in stone at their ancestral castle. He immediately wrote it down as a possible song title, and he and lyricist Ray Evans later respelled it in Spanish "because there are so many Spanish-speaking people in the world."
Ironically, the phrase "Che sarà sarà" is also ungrammatical in modern Italian.
Back to Spanish: this week's song (not related to Que Sera, Sera) is... Qué Será by the Puerto Rican legend José Feliciano.