If your duckling does not have feathers yet, they are unable to move outside because they’ll need warm protection until their feathers arrive and can help regulate their temperature.
After the first week, you will need to lower the temperate by one degree each day until the temperature inside the brooder and the low temperature outside the brooder are the same.
Use a shallow bowl for water so that they can submerge their entire bill to ensure their mucous membranes stay moist, but will not fall into the bowl and drown.