Download LiveGUI USB Image from here: https://www.gentoo.org/downloads/
dd into memory stick.
$ lsblk
NAME MAJ:MIN RM SIZE RO TYPE MOUNTPOINTS
sda 8:0 0 465.8G 0 disk
├─sda1 8:1 0 100M 0 part
├─sda2 8:2 0 16M 0 part
├─sda3 8:3 0 465.1G 0 part
└─sda4 8:4 0 509M 0 part
sdb 8:16 1 14.5G 0 disk
└─sdb1 8:17 1 14.5G 0 part /run/media/cedric/ARCH_202102
nvme0n1 259:0 0 931.5G 0 disk
├─nvme0n1p1 259:1 0 512M 0 part /boot
└─nvme0n1p2 259:2 0 931G 0 part /home
# dd if=/home/cedric/Downloads/livegui-amd64-20230723T170155Z.iso of=/dev/sdb bs=1MB status=progress