Based on your needs, I think it would be best to avoid Linux as an operating system which people will likely try to steer you towards here. A lot of commercial/CAD software will likely be Windows-only and it’s not worth trying to set up a compatibility layer and troubleshooting issues when they pop up.

If you’re looking for a reliable laptop, I can say Lenovo and Dell are generally reliable. If you wanted to go the Apple hardware I also don’t think you could go wrong with a Macbook if you can afford it, which you could install Windows or any other OS on if you need to.

I have a work-issued Dell laptop which can take a beating and is okay, albeit a bit old at this point and due for a replacement. I have a Macbook Pro that I bought in 2013 and is still going strong, but 11 years later is feeling its age. And I have an MSI gaming laptop which is powerful, but I am not sure is going to survive another couple years.

If you want to go the desktop route, you have a lot more flexibility when it comes to specs and you have the advantage of not having all your components on a single board, so that way down the road if a component fails or you want to add more RAM or add more storage space, you can pretty much swap anything out instead of replacing the entire unit. I don’t know if there’s a “Build a PC” community here on Lemmy but if you take a look at the requirements for the software you want to use and look around the internet for builds that meet those requirements, it will help give an idea of what components you might want to buy.

Not to mention, of course, that Dell and the like will also sell prebuilt desktops with hardware you’re looking for, albeit with a bit of a markup.