Baby's First Distro Hop

Yet another distro-hopping question

Hello everyone. I took the advice of this sub and migrated from Win11 to Linux Mint Cinnamon last month and I have a question.

I like LM and the customization Linux offers but I'm not the biggest fan of Cinnamon and I want to switch to a distro with a different DE, preferably KDE, and remain in the Debian/Ubuntu family for now.

Kubuntu seems like a no-brainer but I'm wondering what I'd lose by switching from mint.

What I need:

Different DE than cinnamon (KDE preferred)

Debian/Ubuntu family (i'm putting arch on another machine eventually)

Won't break horribly on accident/update (I'm a college student and need to use my laptop daily)

Also, how do you guys back up your files? I've heard of clonezilla but I can't wrap my head around how it works