This may or may not help, but have a look at ZorinOS. The latest release and it's announcement is targeted towards those wanting to jump ship from Windows -> Linux. They've tried to account for the adjustment with built-in tips/prompts and the UI looks closer to Windows also.
I've actually played with Zorin a bit in a virtual machine. It seemed cool enough, and I tried showing my parents screenshots of it to show them how Linux isn't that different than Windows, but they were unconvinced.
I managed to get Winboat working on my NixOS laptop, so it's possible that if I set that up they could deal with it.
I actually tell people to avoid Arch-based distros for beginners. They can break really easily with the rolling release. Something LTS would be better.
You're right, Office is where you will struggle.
https://blog.zorin.com/2025/10/14/zorin-os-18-has-arrived/