You sometimes have to press a button for using your own bag first

Your supposed to weigh the bag first, at least in some stores.

Yes. Though it depends on what you want. If you are willing to learn some stuff, and don’t mind doing some maintenance, then CachyOS is hard to beat. It’s fast, up to date, has packages for basically everything, and the documentation from both them and from arch linux the parent distribution is great. Otherwise Linux Mint, PopOS, Aurora, and OpenSUSE are all good options. I wouldn’t recommend using Ubuntu directly anymore because of the enshitification canonical have engaged in. Debian is always good, but might not be what you are looking for in terms of ease of use or being up to date.

They also had pretty strict CPU requirements. Mostly only 8th gen and newer, or a ryzen, would be required.