I don’t know if someone reverse engineered the protocol to send light command to this lamp, but even if it is the case, it seems unlikely that the implementation made its way to openHAB.
For the sound part : there is no “audio sink” within the bluetooth binding, so it is not directly possible.
But, if you are on linux, and manage to play something on your bluetooth speaker with pulseaudio (an internet search for pulseaudio bluetooth can put you on the way), you can then send openHAB’s sound to your bluetooth speaker, as there is an “audio sink” within the pulseaudio binding for openHAB.
openHAB → pulseaudio binding → pulseaudio server → bluetooth speaker
But, be aware that openHAB is not a music player. It can play some MP3/WAV if they are put in a special directory and if you create some rule to trigger it, or it can use some text-to-speech to say something, but you cannot browse music in a user friendly way.
If you want something more user friendly, you can install a music server like “logitech media server” or “mpd”, and set them up to use the pulseaudio bluetooth sink for you speaker. (again, if you are on linux, but I suppose it should also be possible on Windows or Mac).
You will then be able to manage your music through their dedicated app on your phone, or a browser, or even with openHAB with the appropriate binding (we have a Squeezebox binding and a mpd binding for that)