Github: github.com/itzMeerkat/Godot-RealisticEnvironments
The ocean effect is based on repo: github.com/2Retr0/GodotOceanWaves and fork github.com/20k/GodotOceanWaves.
I did some optimization and modification on it, with help from GPT.
Also implemented a buoyancy system, day/night lightning system, also with help from GPT.
Hope it will be helpful to someone making your own game.