After extracting the archive to your file-system, the specific demo can be found by traversing to the ../examples/light_switch folder.
You will also need a copy of Segger Embedded Studio, which can be found here.
Note that since you are using the nrf52840, you will need to follow these instructions in order to access the project files for that specific PDK board (assuming you decided to download the latest v1.0.1 nRF5-SDK-for-Mesh, this will hopefully be corrected in future mesh SDKs )
Finally, the default light switch demo assumes you will use 4 development boards (3 for servers and 1 for the client), should you not have this exact configuration, you can follow these instructions, I believe they are still current.
Thank you, but I do not understand what you write about, that I'm using nrf52840 "Note that since you are using the nrf52840, you will need to follow these instructions in order to access the project files for that specific PDK board (assuming you decided to download the latest v1.0.1 nRF5-SDK-for-Mesh, this will hopefully be corrected in future mesh SDKs )" try to explain in another way, but thank you very much for the help
What it means is that the project files to build and run the light switch demo for the nrf52840 board were not included in the nRF5-SDK-for-Mesh v1.0.1 SDK file, so you will need to generate those manually by following the instructions that I linked to.
