Only hollow, arrancar, and vizards can use cero.
Not normally, no. Usually, only Hollows and Arrancar can use Cero. Vizards, which are Soul Reapers that have obtained hollow abilities, are the only ones that can, but I think we've only seen this used in three contexts: Shinji in his fight with Grimjow, and Ichigo in his advanced Hollow form against Ulquiorra and Hiyori during the fight against Aizen
Ukitake has also been able to blast a cero, but that's because of his zanpakuto's ability to imitate the attack his enemy has shot at him. (as seen in the manga and anime, during battle against Stark)