Creating a 3D ground platform

I am new to playCanvas and I am trying to create a configurator. I have decided to have grass on my ground plane.

The following link shows what I have done till now:
https://launch.playcanvas.com/617957?debug=true

In this template the grass doesnt look real. I want to create a ground on which we can see the grass in 3d.

Is it possible?

When I put in a grass model, it streches over the original plane. Is there a way where the grass model does not get stretched and it repeats itself