On the left or right bars on the side, there could be a button for a section that says "Layers" where you can drag and drop each layer to move them, select a certain layer/picture/icon/etc. (the main idea of this. Often, it's difficult to click on the layer you want without moving everything out of the way, even if you can clearly see the layer). When you select the layer there (after maybe searching it in the search provided to support my other idea of naming the layers as an option), you can do everything as usual.