Since I loved the Raspberry PI Zero - I decided to buy the Raspberry PI 4. It is 4GB in RAM with a decent enough CPU. This thing is tiny so it doesn't take up too much space. It can be turned into absolutely anything you want... from a security system with a camera attached to a NAS drive. With the 2 USB 3 ports - expect good bandwidth.
If you're into IT and technology but you don't know how to use Linux... get a Raspberry PI! they come with the Linux distribution called "Raspbian", which is based off the well-known Debian distro. Having the ability to say on your CV that you have knowledge of Linux really does improve your prospects since many organizations run their services off systems that are mostly operated by Linux.
Knowledge == power.