How are Ocean Biomes Generated?

Hi, I'm still very new to datapacks.  I've used the datapack generator for dimensions and biomes, but I've also read on the Minecraft Wiki about biomes, as well as the Datapack Wiki about how certain biome things are handled to an extent.
What confuses me however is how oceanic biomes generate. I know it has something to do with noise; I just don't know how it's handled. I'm just looking to make it where there's large pools of lava (since it's my sea block) to cause it to be listed as a biome.