The quest "The Blocked Well" is part of the "Potential Princess Sightings!" Side adventure in Tears of the Kingdom through which players can earn the Froggy Armor set. To start this series of quests, players need to speak with Traysi at the Lucky Clover Gazette, located at coordinates (-3253, 1763, 0119) in the Tabantha Frontier, where they'll become a junior journalist accompanying a large Rito named Penn.
Throughout Hyrule, players will come across quests from this series at various stables. Here's a step-by-step guide on how to find and complete "The Blocked Well" quest in Tears of the Kingdom.
The Blocked Well Quest Walkthrough
"The Blocked Well" takes place at the Gerudo Canyon Stable, specifically in the nearby Gerudo Canyon Well located at coordinates (-2817, -2233, 0029). While at the stable, the player can also accept and complete the quest "Piaffe, Packed Away.” Unfortunately, the stable has been closed due to orders issued by Princess Zelda. The player will recognize their large feathered friend Penn standing near the well outside.
Penn explains that the Princess has forbidden access to the well, causing a water shortage that led to the closure of the stable. Penn is unsure about the reason behind the Princess's decision and is unable to investigate the well personally due to his bulky size. However, Link can explore the well without any issues, starting the quest "The Blocked Well."
The player should jump down into the well and land in a pool of water. After swimming to the nearby shore, they will encounter a solid wall of breakable stones. To break through the wall, players can either fuse a weapon with a nearby boulder or use a 
Bomb Flower.
Breaking the stone wall reveals a large room with two highly dangerous Black Lizalfos and one Blue Lizalfos armed with a bow and arrows. It is advisable to defeat these enemies from a distance using ranged weapons and projectiles, as the Lizalfos will deal significant damage in close combat. Using arrows fused with Bomb Flowers may be a good strategy for swift and efficient elimination.
Once the first group of enemies is defeated, players will have to face a Like Like attached to the wall behind them. The Like Like must be defeated as well and will drop a chest containing a Radiant Shield upon defeat. Beyond the Like Like, players will encounter an Electric Lizalfos at the entrance to the next room.
The Electric Lizalfos can be particularly frustrating as its electric attacks cause Link to drop his weapons. Additionally, it tends to jump onto the player, making safely and effectively landing ranged attacks difficult. Once the player dispatches this enemy, they can collect various mushrooms in the small cave room.
After defeating all the enemies in the cave, Penn will call out to the player from above, and they will be teleported out of the cave. Link informs Penn about the experience inside the well, and they conclude that the Princess closed it off to protect everyone from the monsters. Penn rewards Link with some Rupees and additional bonus rewards based on the player's current progress in completing the "Potential Princess Sightings!" Quests.
The Legend of Zelda: Tears of the Kingdom is available for the Nintendo Switch.