No device in Home Monitor

Trying to make a security set-up but as seen on this picture I see no devices for my Home Monitor. The text is in danish and says No security sensors.
I have several devices (lamps, buttons and motion sensors).
How can I use already installed devices? When I push the Smartthings Home Monitor I can only attach new devices not already installed devices.
Sorry forgot to attach the picture

@JDRoberts created a faq page so review it and see if it helps. if not, feel free to ask more questions…

Thanks. It was very simple, but only when you know how. Thanks again