Here you can find the source code of my Toon Water shader + Underwater effect you can download all scripts, shader, texture, fbx and everything included in the video scene on youtube. All were made in version 5.2.1f of Unity, and then opening it in an earlier version would be of no use, but in a later one, you may only have to update some lines, although Unity generally takes care of doing that automatically https://youtu.be/2tqrey7VnUI
You can use this scripts or modify it freely, and if you think it was a good job and it is in your possibilities, you can help me get a better laptop by inviting me a coffee, I will thank you very much https://ko-fi.com/spidermeowth