14 days of newborns, the blocked nose, what should i do?

Saline nose drops : Newborns prefer to breathe out of their nose and thus any small amount of mucus sounds very noisy. If your baby is feeding well, you don't have to do anything. If not, then you can put a drop of saline (salt water drops) in front of the nostril, let him breathe it in and out, then suck it out with a nasal syringe. Sometimes closing the other nostril gives better suction.

Nasal congestion: Not fully understanding the question, if its about the 14 day old newborn that has nasal congestion, then suctioning after using saline drops is the best option. Cool mist humidifier can help as well.

Irritants: The first months are troubled by narrow nasal passages & exposure to dust, fragrences, smoke & other irritants aggravates this.Baby tries to flush these out of the nose with mucous but this often ends as congestion & produces rattling with breathing. The best rx is washing out the nose with saline & suctioning the remainder. Eliminate irritants from babies environment & this will happen less.