Indeterminate, as we don't know if there is core of solid matter for a creature to be "on".
Life, if such exists, would have to be the equivalent of what we call "aquatic" life, or in the case of Jupiter, being mostly Hydrogen, "Hydrotic" life.
They would have to be much like our deep sea creatures, only more so, to deal with the enormous pressures of Jupiter's gravity. It is doubtful that intelligent life could develop on a planet in which no fire could be discovered.
Realistically, for creatures to live in Jupiter, one would have to speculate about aliens who had developed on another planet, invented star drive ships, and chose to live in artificial environments in and about Jupiter for the convenience of a near unlimited supply of hydrogen to power fusion reactors.
In actuality, should we ever develop a real space program, living on the moons of Jupiter, and mining the planet for fuel for reactors, would give us a near Utopian lifestyle of plenty and ease.
Every living creature needs oxygen to survive. Just as every living creature needs water to survive. For example, such as spiders. Yup, spiders do to need oxygen AND water to survive, and of course food. So the answer to your question would be yes, snails do need oxygen to survive.
nothing but food
A robot. Humans couldn't survive there.
If you brought along everything you need to survive there ... in other words, everything you need to make it feel like Earth ... then you can keep going until your body, your mind, or your supplies give out. If you didn't bring along everything you need to make it feel like Earth, then you're dead before you leave your landing craft.
you need to have little fur unless your nocturnal; need to store water
There is no way any sort of living organism could live on Jupiter 1st, its gravity is so strong that you would get crushed. 2nd It has an atmosphere made of helium and hydrogen and we need oxygen to survive. 3rd it has very cold temperatures
It is purely speculative as there is no evidence of aliens on Jupiter. However, if an alien did exist there, it would likely need to withstand extreme pressure, radiation, and cold temperatures. It may have evolved to have capabilities to survive in such harsh conditions.
Jupiter is a planet that would be very difficult to survive on. Jupiter has extreme gravity which crushes everything around it. So reducing the effect of gravity would be top priority. Some other needs would be oxygen, food, actual land to live on, and something to dissolve the toxic gases.
A person on Jupiter would need to wear a spacesuit with built-in temperature control and protection from high levels of radiation. The suit would also need to be able to withstand the intense pressures of Jupiter's atmosphere.
you would need a [jetpack]
Every living creature needs water to survive, so in that sense, yes. They also need water for food, because that is where their main source comes from. But they will not die if they don't swim.
they need it to survive