Like for example selecting Linux distro, downloading it and saving on an USB.

Using an USB thing is the somewhat decadent newfangled way to do things. The more classy way was to download the whole distro to an 1.44 MB floppy drive. \installation was by dd .... of=/dev/fd0. Yeah, it required 16 megabytes of RAM. It was possible to boot it on an 386 PC. Though kernel compiles were a bit lengthy.