What to put in the USB?

[bracogem]

Hi,
just a "newbie" to Void here.
At a certain point in the install guide you mention to mount an USB drive in /mnt/usb, but you don't explicit what to put on the USB. What to put on that then? xD
Hoping and waiting for your response. Sorry for the bad english lmao.
Greetings from Italy 👋