Something that surprises me is that no one mentioned just running debian 12 with lxde. Though, I don’t reccomend using the netinstall, as the user created there won’t be part of the sudo group. You should use the live iso.
Lubuntu is based on Ubuntu, which is based on Debian. It meets all of your requirements, and has never crashed on me in my 2.5 years of using it, except when running kde, but that’s probably kde’s fault.
https://cdimage.debian.org/debian-cd/current-live/amd64/iso-hybrid/debian-live-12.9.0-amd64-lxde.iso
If you don’t trust my link (fair enough, don’t click links from strangers), the iso can be downloaded by going to debian.org, clicking “other downloads” under the big “download” button, locating the live isos, in the “Try Debian live before installing” clicking “other live iso”, and finding the lxde iso.





Well, on most distros, the live image is loaded onto ram. Thus, whenever you restart, you lose everything. You could install linux on a usb, but thats incredibly slow, in my experience. If you could detail your problem, maybe we can help you fix it, instead of applying an ineffective bandage.