I am new to Unreal and water systems are not working

Hi, I am new to the Unreal Engine, I am trying to put a little winter stream river into a scene and it takes out all of my sculpting within the mesh and applies the deformation that you see in the screenshot.

I get a build error that says I need a landscape for the water to be rendered. Which is odd because quite obviously there is a landscape. I put in a new landscape and made it an editable mesh, and I got improved results after I restarted the engine. But, I do get that error. It is deforming the mesh now, but it is obviously still not working like it should. Any help would be greatly appreciated.

I found out that the landscape was too small.