The oxygen You can’t breathe mars oxygen because it is carbon dioxide so you have too have to get a tank of oxygen so you can breathe
You need water so your throat will get dried up and you get sick and you can’t talk. But there is a machine that clean your pee and turns into freshwater for them to drink so they don’t die with dry throats.
You can’t bring food on the spaceship because it is too heavy but they can build a greenhouse that you put your planets and food in to grow that’s how what they eat different type of fruit or plants.
They are no houses on mars and no doors normal food but they could make a little shelter for them with the dust which is on mars and it will be sticked just like a bouncy house and they put all their stuff in their little shelter.