Complex sentence: On July 12, it was announced that Young-min and Dong-hyun will debut as a project unit, the duo with both members having signed exclusive contracts with Brand New Music before "Produce 101" and becoming members of Brand New Boys.
Split into simpler sentences: On July 12, it was announced that Young-min and Dong-hyun will debut as a project unit. Apparently, the duo had signed an exclusive contract with Brand New Music before "Produce 101" and became members of Brand New Boys.