Everyone, who use Unity, knows about Universal Render Pipeline (URP) or Hifh Definition Render Pipeline (HDRP), both scriptable rendering that includes a visual shader graph programation, if we want we can compile it like a shader file, it has a big potential.
There are many tutorials that teach how to add water using shader graph, so why you sholud download this package?
So if you want it optimized for mobiles phones you should download the lite version (Only for URP), this packages now are child, but in a future they'll be adult with their help tools, (Including the Free Version), but now we don't know how to do that. "we are new doing this either programming or using unity, but it doesn't prevent us from helping " - Direction of ABKaspo Games. We used unity just 3 years, before we used Eclipse IDE, we mean Java, the two languages are similar but they've their differences that it'll take us time to learn.
Now you are watching the AURW documentation: