In The Legend of Zelda: Tears of the Kingdom, the Jonsau Shrine can be found in the Lanayru Wetlands on the southern side of Mercay Island.
Enter the shrine to begin the Deep Force challenge. For the first obstacle, grab the ball using Ultrahand then bring it underneath the target. Push it far under the water as you can then let go! It will bounce up to the target and the path forward will open. Head through the gate to reach your next challenge.
In this room take out the Construct then look in the water to find a chest. Pull it up using Ultrahand then open it to receive the Strong Construct Bow. Return to the previous room and grab the ball. Bring the ball with you to the next target. Again, pop it under the water then let go. This will open the path forward.
For the last challenge, pop the ball in the room under the water near the center of the structure. When it flies up, the wooden pallet will fly off freeing the lift. The lift will then drop into the water. Swim to the lift and stand in it then case Rewind on it. You’ll soar up into the air and when you reach the top, step off and make your way to the altar. Examine the altar to receive a Light of Blessing.