The camera is one of the fan-favorite features in the Zelda franchise, and you don't get access to it from the get-go, but you need to instead complete a quest to be able to use it in The Legend Of Zelda: Tears Of The Kingdom.
In order to use your camera, you need to first complete the Camera Work in The Depths quest in the Legend of Zelda: Tears of The Kingdom, which can thankfully be unlocked quite early on in the game.
Start The Camera Work In The Depths Quest
In order to start the game, head to the Lookout Landing, and you will find Josha and Robbie there. Speak with them to get Arrows and Brightloom Seeds. The latter is going to be quite useful for your quest as it helps you to light up your surroundings, and the area you need to head to is filled with darkness. As soon as the quest kicks off, you must rendezvous with Robbie at Hyrule Field Chasm, which is right south of Lookout Landing, where you had gotten your hands on the Paraglider and spoken with Robbie and Josha. If you have already been to the Jiosin Shrine, then you should be able to find the Chasm without breaking a sweat, as it is quite close to it, right towards the north. The Jiosin shrine is located right on the territorial boundary, and if you are making your way towards it from the Lookout Landing, you should be able to find the Chasm on the way.
Jump inside the opening on the ground, and use your paraglider to avoid getting damaged, to reach the Depths. Inside the Depths, you will come across the Zonai Survey team camp and will meet Ponnick, who will give you some hints about Robbie's whereabouts. Ponnick will point you toward the direction of fire. It is quite hard to see here, thanks to the darkness, but your Brightbloom Seeds are gonna be of ample use here. Head towards it, and you will find a glowing green aura at the base of a root, the Nisoij Lightroot, right before you reach the fireplace. Interact with it to not only create a fast-travel point but also get some much-needed illumination.
Rendezvous With Robbie & Take A Snapshot
From there, you need to keep heading west, and you will find multiple camps and fireplaces on the way. You will get a few notes from these camps, so make sure you grab them on the way. To get an idea about where you exactly need to head, you can simply look for the next Lightroot. It isn't that hard to spot it, and you should be able to see it after heading a bit toward the west from the first one. As you approach the Lightroot, it's going to get darker and darker, and you need to avoid the gloom on the way as well. You can illuminate the area to take the enemies out or simply avoid them and head straight to the Lightroot. Once you reach the Iayusus Lightroot, look for the nearby fireplace to find Robbie and then interact with him to get your next objective.
Be wary of the Gloom status effect in the area, which you can get from certain enemies and by coming in contact with Gloom. You need to stand in sunlight to get rid of this, and it depletes your maximum heart as well.
After you have interacted with the Iayusus Lightroot, speak with Robbie again, and he will ask you to take a picture of the statue, which is right near the fireplace. Grab your camera and take a snap. Once that's done, you need to return to Lookout Landing to speak with Josha. Once you have completed the quest, you will get five Zonaite quest rewards.