1.At 0°C water can exist as a solid as well as a liquid. There will also be a small amount of water vapour in the air above the water/ice mixture.
2. At 100°C water exists as a liquid , with a large quantity of water vapour above the surface. For this one - look inside a kettle of boiling water - If you measure the temperature of the water it will be 100°C - you will see a large amount of condensed steam also at 100°C above the water surface