This might be an incredibly stupid question, but a first time to everything I guess.. I want to install a smart radiator thermostat to and I need to remove the old one. Can I just remove the screw and pull it off or will water come out?😅😅

I want to install the thermostat on pic 3. I’m really new into DIY stuff and I don’t dare to just take this old knob off because I’m afraid that water will go everywhere. I found videos where people just pull it off without anything happening whatsoever and some videos where they try to reinvent the wheel to install the radiator thermostat. Can someone give me any advice on this?

I also could not find anywhere online or in the manual if I need to remove the old one while it’s fully opened or fully closed. I’m not sure if it matters for the new thermostat or not?

Thanks in advance for any information.