Proxmox and Docker serve different purposes. There is a little bit of crossover when it comes to containerization, but that’s really the only commonality.

If you want to run multiple services and have a playground to mess around with, Proxmox is what you want. Spin up a VM (or 2, or 3) for Docker, and run your Docker services in those. You still have the ability to dick around with other things in Proxmox without having to worry about fucking up everything else on the physical machine.