Whatever you’re most comfortable with. It’s a simple enough ask that you can do it in Ubuntu server or Debian quite easily.

I would recommend at least using docker but you don’t have to.

Truenas isn’t very forgiving with drive configuration. I really like it but it isn’t great for randomly adding drives here and there. Unraid might be a better choice for home usage. I have never had good luck with their built in app stuff but I’ve also never really tried past it not doing what I want.

I run truenas with a ubuntu server vm and docker some stuff in that. I also run proxmox on another server and a dev server running Ubuntu server that I docker things on.