The low cost Arduino clones are fitted with the CH340 USB interface chip that will need some software installing for your computer to be able to communicate with it.
It’s a simple matter of downloading the driver from here and running the installer.
The alternative is to buy an Arduino with an FTDI FT232RL chip on. A branded Arduino comes in at around £20. A clone with this chip on can be had for around £10 locally, £4 from China.