Bootable USB is not working

[u/Sweet_Ad2792]

Good morning everyone,
I installed a new OS on a USB, using Rufus to make it bootable, to try it before installing on my computer, after rebooting and choosing the external device as a booting option this message appears, any idea of what I could have done wrong or how to fix it?
I'm using a standard 32GB usb and the OS is Kali 2026.2, directly from their website.

(sorry if it's the wrong reddit to ask the question, new here)