No, you should not put water under the microwave oven. The microwave oven is designed to heat food and liquids placed inside it, not underneath it. Placing water under the microwave oven can be dangerous and may cause damage to the appliance.
Water should never come into direct contact with the electrical components or the heating elements of the microwave oven. Doing so can result in electrical shorts, malfunctions, or even electrical shock hazards.
If you need to heat or boil water, it's always recommended to use a microwave-safe container or a kettle specifically designed for that purpose. Follow the manufacturer's instructions and guidelines for using the microwave oven safely.