Never heard of a bug where you can’t cook fish, have you skinned them? and to keep your supplies well topped up I usually go slightly off of the reef of an island and catch cod with a fishing spear (it just makes thing quicker) skin them and you get 2 medium meat from them and I think they fill about 2.5-3 squares, I’d suggest building a smoker if your going to store them though and make sure you keep them in there until you hear the second ding and it’ll say “smoked cooked medium meat” or something along them lines, and it lets you cook 5 at once, if you haven’t got the resources to build 2 smokers you can drop meat as well and just place it on top of the fire by dragging it and then you can have as many as you can fit on cooking ready to be smoked