

https://www.fedoraproject.org/ https://linuxmint.com/ https://archlinux.org/ https://www.debian.org/ https://elementary.io/ https://system76.com/pop/
There are many safe open source options. If you need help there are ample resources available. If you want to you can also DM me.
Depends on what software. Anything that happens in the browser works. A lot of other software can be run using Wine. There is some software which still has problems especially when using USB ports as serial ports etc. and a lot of subpar software (un)fortunately just doesn’t work because of it being badly programmed.