Venus has a thick layer of sulfuric acid clouds, veiling its surface from the observers on the Earth, which move very fast due to the rapid circulation of its atmosphere. After all, it’s much closer to the Sun than the Earth while having enough greenhouse gas for the temperature on and near its equator to soar and cause a violent climate in its upper atmosphere. Isn’t that enough hydrogen for us to make water?
Well, as every commander should know, keeping is always the hard part. So, you somehow find a way to mass-produce water from sulfuric acid clouds by removing sulfur and depositing it into a separate container, somewhat like a vacuum cleaner. Now, water is to be collected into large tanks to be dropped with balloons or parachutes. It will work, but the lower atmosphere of Venus is not ready. Venus is still too hot at this point.
So, we want to modify its lower atmosphere first, just to cool it down and make it breathable. By lowering the temperature of the lower atmosphere, we will also grow the sulfuric acid clouds vertically, downward, that they will eventually be ready to rain. Long before that happens, we collect water as previously described, so that we will have many large water tanks in a few selected areas. There’s simply not enough hydrogen on Venus that we can afford to let it into Venusian soil and disappear.
Now, you’ve got only one chance to do it right. If you lose, you lose. Make sure you have planned every single detail to guarantee a success.
Otherwise, a nuclear fusion engine is still the best bet with submarines and spaceships that are biospheres of their own. If you can’t build societies in space, build teams. Now you ask how these teams can form a decent economic entity other than performing military operations. There are simply not enough people in these mini-biospheres. Well, they can do scientific research and sell their results. Of course, you have to manage them properly, because scientists love meaningless research projects, which I call a benign form of corruption. They aren’t necessarily evil. They are just curious.