You don't really need hydrogen in elemental form. You do need hydrogen to make proteins and nucleic acids (and lots of other compounds), but normally you'll get all you require in your diet ... hydrogen is the most abundant element in the universe, so it's kind of hard to run low on.
To answer this question we would need to know the substance from which the hydrogen is to be removed.
hydrogen makes water and you need water to live
we need hydrogen because without it there is no water and we will get dehydrated without water
Hydrogen and oxygen are similar because we both need them to survive hehehe
No
hydrogen
depends how far you want to go, the hydrogen would need to be compressed or liquid
Hydrogen is a major component of carbohydrates, which our bodies use as an energy source.
No, you would need energy to combine hydrogen and oxygen into H2O
You don't need to, they'll do it on their own. Individual atoms of hydrogen are not chemically stable and will spontaneously recombine.
Since hydrogen is a gas, we would need more information to answer it. As chance wrote, you will need twice as much hydrogen as oxygen. However, in order to know what the volume of that hydrogen is, we also need to know the temperature and pressure so that we can use the universal gas law to get the answer.
twice as much hydrogen to oxygen