This is always a funny one. Everyone has different ways of doing things, but there is always an area of agreeance across the spectrum. If you have a computer setup with control software that is dedicated to running a machine, keep it at that and nothing else. I have 3 very expensive $8-$12K desktops (not required at all for the vast majority of people who do a TON of manufacturing) and 2 of these only run CAD with one of them running both CAD and CAM. Each one of my machines have a dedicated computer that will run the machines and run the code produced from my CAM (CAM is on another computer). I also have a single centralized computer (3rd comp with all software) with everything installed so if you need to make product mods on the fly during manufacturing, you can make small iterations in near the machine (my facility is 50,000 square feet, so it cuts down on walking back and forth from the master CAD/CAD setup). But in my personal shop, I run 2 computers, one is for CAD and CAM, and the other just runs machines which reads the code produced from the CAD/CAM computer.
So good practice is two computers, nothing complicated for the one that runs the machine, and one a bit on the higher end for the computer that will be doing CAD. Now at home, I have a high end desktop that I CAD with and CAM with, then I save the code to a share drive. From this share drive, I run the code on my machine computers. It's just a good practice to keep your machine's operation computer clean as possible, as if it's only job it to run your machine. As far as desktop vs laptop, I have no opinions on this, they are all great, I just prefer desktops. Running a dedicated comp for your machines helps to eliminate code glitches or various processing errors that can result from various stages in update or program patches. I am almost 2 million dollars into my fiber laser setup, so protecting it's controls is super important along with all my other CNC's. Think of it as compartmentalization, gives you way more control and a smaller problem to troubleshoot when the machine does something out of the ordinary. Lastly, Happy Retirement and congratulations!