I’m sure a lot of you know, but maybe some don’t. I found out how to do a pretty basic shoreline in Unity (works with the free version of Unity) I looked for an answer for soooo long and couldn’t find one.
Today I was going through my particles folder in my Standard assets. In the folder labeled Water (obvious, huh?) there’s a prefab called " Water Surface Splash " I used it in my project and tweaked it, and oh my, it looks so good! 
This is so helpful, and if you’ve been looking how to do the shoreline that’s in the Island demo, this should help you greatly.
That’s all, I hope I helped somebody a whole lot. 