It’s not easy to build stuff on the moon but it doesn’t mean it’s impossible It’s way too expensive to take material from Earth and bring it on the moon. One kilogram of building material cost $25,ooo and 1 kilogram won’t build much. So only way to build on the moon is to use available stuff on the moon. One thing that moon have plenty is moon dust. Scientists found moon dust mixed with another substance found on the moon, called sulphur can be made bricks. There is another interesting question “How would you gather enough moon dust to make all bricks needed? Scientists come up with a vacuum cleaner that can collect moon dust ready to use. It will be still long time to these things reality.