Painting Textures

I am wondering if it’s possible to be able to paint additional textures onto a landscape while using a landscape material which is used to sculpt the land entirely. I’m trying to add them via layer blend but it doesn’t seem to work. I am using the “Landscape Mountains” material to sculpt my land which I found on the learn tab of the epic launcher.

I basically want to be able to pain other textures such as snow footprints, paths and so on but it seems I am restricted to the materials that are being used in the the Landscape Mountains material.