Hardware requirements: it should have a keyboard and a screen. And, if it doesn't have a touchpad: a touch screen or a port to connect an external mouse to. And preferably it should have an Ethernet port or WiFi to be able to use Internet, although a second USB-port can be used for that also. The storage (hard disk or SSD) should be big enough for everything you want save on it, including the OS and the programs,.
And, of course, it should meet the recommended hardware requirements of the software you are planning to run on it. But since you didn't tell about that, we can't advise on that.

Software requirements: it must come with Linux, Windows 10 or MacOS, unless you prefer to install those yourself.