The monitor should be able to be attached from the wall and have the following properties:
speaker
Wi-Fi connection or wireless connection with my laptop
Mountable on the wall
1920 x 1080
at least HD quality
ideally black
possibly also a touch screen if possible but not a must
possibly also usable as a TV
Here are monitors
1920x1080
Wireless Internet access
speaker
from 27 "
I recently wanted to set up something similar for a video conference.
So the laptop has to be in the immediate vicinity of the television - actually it doesn't even have to be a laptop → a mini desktop PC is enough.
Then you need a wireless keyboard (I almost recommended one with a touchpad) You then connect the monitor to the laptop or MiniDesktopPC.
A mini desktop would have the advantage that it could possibly also be hidden behind the monitor / television.
If I were you, I would buy a TV directly and connect the PC to the TV via HDMI.
My favorite brand of televisions is Panasonic - they have really good picture quality. I might recommend a Panasonic TX-40FSW504 40 inch / 100 cm Smart TV