After installing TorizonCORE for the first time, it shows a portainer.io user interface.
Where I can see that 3 containers are running, but I can not see them.
I tried to attach them to them, but it did not work.
How do I see them in action?
You have 3 containers: Weston, Kiosk Browser, and Portainer.
Weston is the container that lets Kiosk Browser make use of the Weston graphics stack (here you can include GPU accelerated stuff, if available)
Kiosk Browser is the web browser itself. Without this one, you would not be able to see the Portainer page on the monitor/display connected to your module.
Portainer is the page that you are actually seen. This is only possible due to the functionality of the previous containers.
You can actually attach/exec some of the containers. But it you only attach, you might end in a non-interactive shell, because of the nature of the process running.
For weston container, e.g. you can:
docker exec -it weston_container_name sh
This way you will drop into a shell that is running from the weston container.