The LayoutEditor will normally start with the layout window. To get the schematic window you can ether open it via Menu/Utilities/Netlist Tool/Schematic from the layout window, start the LayoutEditor with the option '--schematic' or use the Library Manager. With any opening of a schematicwindow from the layout window or the other way round both windows will be link. A netlist from the schematic will be availabale in the layout window and by activating a device or net in the schematic the device or net in the layout window will be highlighted. This works in both way. From the schematic to the layout window and from the layout window to the schematic window.
The performed action will depend on the current state of the design. So in case the device in not yet placed in the layout window, the layout window will be set in the place cell mode with this device. A click on a net may set the layout window in the manual routing mode and showing the required connection, if net netlist is extracted yet. In the cell is already completly routed and a netlist is extracted the extracted net is highlighed as shown here:
A part of the linkage feature will run without any special setup other will require a little bit of setup. So for example to get the net highlight running the order of the technology layers must be defined. Sometimes this is automaticly done in case the PDK of your foundry contains all releavant information.