Unfortunately, you must have this confused with Majora's Mask. The Zora Mask in Ocarina of Time is just for show and is removed as soon as you set foot in the water. Believe me, I've tried.
The Zora King will give it to you went you unfreeze him with the blue fire
blue fire. put it in a bottle; pour it out on him.
Ice Cavren. In Zora's fountain as adult link
Most of them are in the water in Zora's Domain. But seven years later they're under the ice in Zora's Domain.
you need to get the zora tunic
Get the silver scale in Zora's Domain, then go to Lake Hylia through the warp door. The letter is near the door at the Lake Hylia end.
(assuming this is for Ocarina of Time) as an adult purchase it for 200 rupees from the shop in Zora's Domain.
Requires:Access to the area behind King Zora, Bombs, A Magic Meter, an ocarina, zelda's lullaby. To get Farore's Wind in Ocarina of Time, become kid Link (again?), and enter the area behind King Zora. Swim over to the place with the big boulders, and bomb them. Then play zelda's lullaby and talk to the fairy. You will then have Farore's Wind.
Breathe under water
There are a total of 7 Zora Eggs in "The Legend of Zelda: Majora's Mask".
After you get a bottle-full of Blue Fire from the Ice Caverns, return to Zora's Domain. The Zora King is frozen in red ice. Use your bottle of Blue Fire and melt him. He will give you the tunic, free.
There are 4 bottles available to obtain in the Legend of Zelda Ocarina of Time and you can recieve them by doing the following: Find the 3 super cuckoos in the super cuckoo minigame at Lon Lon Ranch, Find all of the cuckoos and bring them back to there pen in Kakariko Village then talk to the lady by the pen, Dive underwater near Zora's Domain at Lake Hylia to find a bottle with a letter inside show it to King Zora in Zora's Domain and he will let you keep the bottle, Find all of the Big Poes scattered around Hyrule and show them to the Poe collector in the Market (she's in the first door by the entrance).