You're very confused. You're attacking points no one made and going off on tangents that are not relevant

"Hydrocarbons" encompasses a huge number of compounds that includes crude oil.

Largely irrelevant. Any small body we decide to visit out past Mars has huge deposits of either hydrated minerals, ice, or has other compounds that can be broken down into hydrogen and oxygen.

Fuel cells generate electricity. They're not used for propulsion.

I'm not sure Callisto belongs on that list. It's largely undifferentiated and not likely to have large pockets of water, let alone an entire ocean. But it's been a while since I've read anything new about it that assessment could have changed.

🤣🤣🤣

Makes my teeth feel clicky

Bland but super crunchy