Snowcapped preview help

Hai everyone! I'm trying to add more biomes into my dimension using snowcapped but the preview doesn't show the right information, my oaceans are much smaller than on the preview. As I see there is a description about this: https://github.com/jacobsjo/snowcapped/wiki/Custom-Inputs-and-Terrain But I'm dumb and cannot really get my head around it. I see that I should make a file named snowcapped_surface in the namespace folder of my datapack. But I have no idea what I should put into that file. Like snowcapped generates my noise settings, do I have to get the final density object out of the json and put int into the snowcapped_surface file? I'm really not sure.