In this tutorial you will learn how to adjust a layer’s opacity in QGIS so that you can “see underneath” or through the layer to the map data below.
In the QGIS layer list, right-click the layer you would like to adjust the opacity for.
In the properties menu, select
Used widgetsby selecting
Opacity sliderand clicking the right-hand arrow
Add selected widgets.
The text “opacity slider” should move over into the Used widgets box.