This Manga is overly complicated for an isekai. Main character died and reincarnated but essentially is transported as himself to a new world at the same age and same body. Think Tom Hanks in Castaway as a comparison for story. He is just strengthening up and trying to figure out water magic so not much to the story.
"Oh no, I'm stuck with this skill!" Skill in question = The Best and Most Useful Skill TM
Sorry, not sorry, pal. Can't relate. AT ALL.
Edit 1: The intro? Way to ruin the mood. What a choice by the adaptors. The novel does not do this to you, it just starts like normal isekai.
Edit 2: Wow. Manga is actually an improvement on the novel. Did not expect that. Apologies to the adaptors. Clearly they did the best they could, considering what they had to work with. They actually succeeded in condensing half(!) of the novel into a mostly readable format.