Our hero Link is awaken by a voice in a weird dark and futuristic-looking room and emerges from a sort of survival capsule. Get close to the lighted altar and take a look at the Sheikah Slate. Take it, and then a door will open. Go forward, then open the two chests which contain an Old Shirt and some Well-worn Pants. Open the pouch, put these clothes on, then go to another terminal. Place the Sheikah Slate on it, which opens another door leading outside. Following the voice's encouragements, climb the steps, run, climb the wall, and go outside.
After gazing upon the landscape and taking note of a man, go right and pick up a Tree Branch on the ground. Get close to the red mushroom next to the tree and pick up this Hylian Shroom. Pick up some more mushrooms and branches if you want to, then walk to the man. Pick up the Baked Apple next to the fire and talk to the old man. Ask him around, he says that you are currently in the Great Plateau, the cradle of Hyrule Kingdom. He points to a temple where ceremonies used to be conducted, but it's been in ruins for a hundred years just like the kingdom. Go down the path and pick up the Woodcutter's Axe on the right. If you want to, you can use it to chop down the tree to the left and pick up the fallen Apples. If you keep going down the path a bit and you climb the small wall next to a tree on higher grounds, you can find some Acorns on the ground.
Avoid or attack the Bokoblin with the axe, then climb up the path a bit, go left, run towards the headland and jump into the water in the middle of the water lilies. A Korok appears and gives you a Korok Seed to give to Hestu, another wood fairy. He says that there are several other Koroks scattered around Hyrule. Swim forward, climb atop the rock and pick up the Rusty Broadsword! Equip it from the inventory (be careful as it can break quite fast), then dive, swim and head to the cracked rocks south. Climb the wall, then go west (on the map) to a Bokoblin campsite. Attack them with the axe or the sword (or even a tree branche), and pick their weapons (Boko Spears) as soon as you can. Pick up also the Pot Lid and equip it as a shield! If you have lost half a heart or more, eat a Hylian shroom or an apple to get some energy back. Take some Spicy Peppers on the small bushes, as well as more Hylian Shrooms, then go next to the fire and pick up the Seared Steak ^^
Temple of Time Ruins
Now aim for the big temple and wander around the temple's ruins. Next to a pond, fight with a Bokoblin, then pick up its Boko Club and its Bokoblin Horn. A little further east, hit another Bokoblin, pick up its club and its horn, then open the old chest which contains some Hylian Trousers and put them on. Climb several sets of steps, fight another Bokoblin and enter the building. Go right and open another chest holding a Traveler's Bow. Lift and toss the pots around to find some Arrows. Go to the back to the statue and pray. In these ruins you can see remnants of Guardians, look at them to find small objects like Ancient Screws and Ancient Gears.
Leave the area and go eastwards, following the direction given by the Sheikah Slate (yellow blinking dot). If you want to, get close to the two rolling rocks on your left and push them so they crush the two Bokoblins below. Get to them and pick up their Clubs and Horns. If you encounter Chuchus, hit them to get some Chuchu Jelly. If you see some yellow flowers, pick these Hyrule Herbs. Look to the right, you will see some stairs and a rolling rock at their top. Climb these stairs, then take note of the Bokoblins and the red barrels below. Push the rock so it blows up the barrels along with the enemies! Then jump down and pick up the Horns, maybe a Fang, and the Club. (If your weapons slots are full, it's possible to leave behind a weapon about to break to pick up this brand new club.) Keep going until you reach the yellow dot, then look in the rocks to find another terminal. Place the Sheikah Slate on it, then some tremors happen and a huge tower rises!
Great Plateau Tower
You then end up atop the Great Plateau Tower. The map of the area is recorded. A voice says that you were asleep for a hundred years, that a demon is getting his full power back and that you have to hurry or else the kingdom will be doomed. Look at your surroundings, then carefully go down the branch-looking ladder, then jump on the balconies until you reach the ground. The old man reaches you thanks to a gliding clothe. He tells you about Calamity Ganon whose curse shrouds Hyrule Castle. A hundred years ago the Calamity laid desolation and death upon the kingdom, and is now held back as a prisoner within the Hyrule Castle's walls. The old man says you need a Paraglider to go to the castle and is willing to let you have it if you find a treasure. Follow him and talk to him when he stops, he shows you the shrine withholding the treasure. Go to this place, jump into the lake, swim across and climb on the other side. Go forward and place the Sheikah Slate on the terminal. A warping point is created and the entrance is unlocked. Take a look at the circle, it is in fact a lift...