I went Proxmox when I was in your shoes a few months ago.
It installs like a Linux OS so you already know how to do that.
You get a webui to work from.
From there, YouTube is a massive help. Watch videos on "how to install WHATEVER on Proxmox" and just replace WHATEVER with whatever you want to prod until it works.
My first service was Home Assistant, which I already ran on a Pi. I had that fully migrated in a day giving me a spare Pi.
Next it was Portainer, and used that for Adguard and Uptime Kuma, and then I got fancy and threw secondary servers of those services on my pi and put that on the network as a fail over.
So yeah, just install it and try to do shit, YouTube is your friend.
Over the last few months I've made a whole bunch of different combinations of VMs, LXC and Docker until now, where I have Home Assistant, a NAS and a Debian server which I deploy docker stacks into.
At one point I had about 15 different machines I could spin up, but now it's just the 3. The great thing about Proxmox is you can just create and destroy to your hearts content