Creating heat map based on attribute from another layer in QGIS

I have a layer showing different trails in a nature areal. For each trail, there is an attribute with the usage of the trail (no. of people passing a trail counter). I now want to create a new layer as a heat map, based on the attribute. How do I do that?

I only know how to do in the original trail-layer, working with the symbology. But I want the heat map to be showed as a separate layer, since it’s easier to work with the original trail-layer. So, the heat map should automatically load the geometry and attributes from the original trail-layer.