Your adventure begins in Lynna Village. After the initial cutscene where Veran possesses Nayru, you'll find yourself in the Present. Your first task is to speak with the Maku Tree, who will inform you of the impending doom and the need to collect the Essences of Time. The Maku Tree is located in the Maku Road area, just north of Lynna Village. You'll need to navigate a few screens to reach her.
Upon reaching the Maku Tree, she will be withered and weak. She will instruct you to find the first Essence of Time, located in the Spirit's Grave. This conversation officially kicks off your quest. Before heading to the dungeon, it's a good idea to explore Lynna Village and stock up on any available items, though your options will be limited at this early stage. grab the Wooden Sword from Impa's house if you haven't already.
Much like the guardian owl in The Legend of Zelda: Link's Awakening, the Maku Tree serves as the primary narrative guide who directs Link toward his next dungeon objective.