using package with a robot

[Wanja1204]

Hello, I wanted to use the aruco detector for a robot with intel realsense camera, which already publishes the following topics: /loomo/realsense/rgb/camera_info
/loomo/realsense/rgb/compressed
i'd like to subscribe this one with my detector, but i'm new and i'm probably doing something wrong, maybe you can tell me, under which line change for subscribing known topics must be done