I got the sprouted plant and talked to the old woman. She siad it must become the treasure and then that plants need loving care. What do I do?
Go back to where you planted the plant in the water.
Climb up to the beam above your head and swing over to the movable platform which opens the window and makes the plant grow.
Put the pot back in its holder, climb onto the beam above and jump on the platform
in the middle at the front to open the window.