How to make a completely standalone linux system on a flash drive?

Question

linux

Hello, I want to make myself a usb flash drive with a full-fledged portable linux system (ubuntu),
so that I can come to a friend's house and boot there (something like a bootable version of linux that boots on any computer). I searched on the internet, there is only info on how to install it on a USB flash drive and use it on your computer, not a word about portability. I tried the option with the usual installation, but as a result, I can’t see the USB flash drive in the boot menu of another PC, which means I can’t boot from it.

Answer 1

1. Boot from a bootable flash drive, open gparted and remove the efi and boot partition flags on your stationary Linux system
2. Install to a flash drive in normal mode, as usual, but on a flash drive
3. Reset the flags to your main system
HERE

Answer 2

Everything is very simple
Fairy tales are deceit... (C) Andrey ben Makar, formerly A. Makarevich
Loading. If a device requires only UEFI boot, then it will never put media without an EFI partition into the boot list, that's all.