I would stay away from kubernets/k3/k8s. Unless you want to learn it for work purposes, it's so overkill you can spend a month before you get things running. I know from experience. My current setup gives you options and has been reliable for me.
NAS Box: Truenas Scale - You can have UnRaid fill this role.
Services Hosting: Proxmox - I can spin up any VMs I need and lots of info online to do things like hardware passthrough to VMs.
Containers: Debian VM - Debian makes a great server environment as it's stable and well supported. I just make this VM a docker swarm host. I managed things with Portainer for a web interface.
I keep data on the NAS and have containers access it over the network. Usually a NFS share.