Astronauts need sustance in order to live and work in space. For example in ISS (International Space Station), the amount of food required is estimated to be about 1.83lbs. (0.83kg) per meal per day. And about 0.27 lbs. (0.12kg) for the packaging box.
Therefore 0.95kg per meal. Three meals per day weighs 2.85kg (credit:https://www.nasa.gov/vision/earth/everydaylife/jamestown-needs-fs.html)

Water is a byproduct of fuel cells. The combination of Hydrogen and Oxygen makes electricity. However in ISS, electricity is derived from solar panels rather than fuel cells so no water is produced. An astronaut normally uses about 4.4 liters of water per day.
1 liter of water = 1 kg. So 4.4 liters = 4.4 kg per day
(credit:https://medium.com/illumination/space-day-saturday-ae1cda0625b5)

As for oxygen according to NASA, in ISS the average person requires around 0.84kg of oxygen per day.
(credit:https://www.quora.com/How-much-oxygen-does-an-astronaut-need-per-day)

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Water Required:
Oxygen Required:
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Water Required:
Oxygen Required:
For x number of persons

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