There are no direct buses from Zadar Airport to the Island of Pag, If you wish to travel to Novalja or town Pag by public bus, you should first take the airport bus from the airport to the main bus station, from where the buses to the Island departure. From the airport you also have option to arrange a transfer to town pag or to Novalja, you can see transfer prices to town page here, and to the Novalja on Island here.