I’m stuck on an island on an incredibly cold and stormy planet what do I do?

Hi there, I came to a super harsh planet for a mission, the mission was on a very small island, but I ran out of launch fuel, the planet I’m on is incredibly cold and storms are frequent even on a good day with no storms planets get your health down triple fast and I don’t know what to do. I’m stuck on an island and if I try to swim in the water I’ll die if I try to go underground or drown, I don’t know what to do get dihydrogen (there is no uranium on this planet either) for my launch fuel please help. I am on planet Diken Prime in Keharasa XVI system with a base on Tegrasilv XII.