The friend should play Kerbal Space Program. It will be a fun way to show that yes, it’s really hard, but it is possible to play around with orbital mechanics and get to the moon.

And then it will show that an unsteerable rocket with infinite fuel and a chair strapped to it is also possible, just really really hard.

This is just my experience, but that experience includes travelling through some remote areas in less developed countries. Water to wash is usually the first upgrade on the tech tree- It’s unlocked right after you dig a hole in the ground. Grinding xp to get plumbing will make life nicer, but to start with you just need to gather enough resources for a bucket.

Added water infrastructure? My guy, the connection for the cistern is right there. The added infrastructure is literally a tee piece and the hose.