I have installed and re-installed Proxmox probably 8 or 9 different times messing around with different drive configurations. The first thing I would say is you are likely to do the same. Its just a fact of life as you learn. My current configuration is a HP elitedesk 800 G9 - 1 liter PC as my main Proxmox host at the moment. It has an intel i5-12500T processor and 32 GB of ram. For reference I am running two LXC containers (Leantime and Tracks), two VMs as docker hosts (one on my trusted VLAN and one for my internet facing VLAN). I run 14 different docker containers: Grocy front end, Grocy back end, 4 different Cloudflare tunnels, 2 instances of watchtower, Heimdall, Uptime Kuma, Portainer, Portainer agent, some maria DBs, photoprism, and a couple others I am forgetting). I also run two VMs running Wordpress and one VM running Nexcloud. My drive set up is two 1TB NVME SSDs in a zfs mirror that serve both as the boot drive and the VM drive. I think I am using about 40GB all total on that mirror. I run very small VMs. My default is to start them out at 8GB and expand them as needed. I have a NAS mounted as storage in Proxmox, and all of my backups, ISOs and container templates go there. The NVME drives have been in service in one Proxmox machine or another for a year now and they have zero wearout according to smart. They are nothing special, just Team brand pcie gen 3 drives.I have disabled the folliowing services since I don't run a cluster: corosync, pve-ha-crm, pve-ha-lrm. I read that doing so will reduce wear and tear on your SSDs. I also have another NAS that I mount all my docker volumes to as well as have SMB mounts to NextCloud and Wordpress. So I have very little actual data sitting on my proxmox machine. All my VMs and LXC containers are backed up nightly
On the other side of the coin, my old proxmox server was an HP Z-640 with a 20 core Xeon and 64gb of ram. I had installed an icydock in it that would hold 6 2.5 inch SSD drives. I had two 256 GB SSDs in a mirror as the boot drive, two 2TB SSDs in another ZFS mirror as storage, and I had the two NVME drives in an Asus Hyper M2 PCIE adapter. I also had two spinning drives that were passed through to an instance of Openmediavault.
I have seen folks with a lot more drives than that in a Proxmox host, but for me, I decided that I wanted to run my pfsense firewall in its own hardware, so that everytime I take down my proxmox host, I don't trash the family's internet. I also like having my data reside off of the proxmox host, so I now have two NAS devices (a synology and a terramaster) each sitting on different VLANs (similar to what I do with my docker hosts), and a third "NAS" that I made out of a Raspberry Pi 4. Both my Terramaster and my Synology back up nightly to the Raspbery Pi and to the cloud. This way I have 3 total copies of my data, 2 onsite, and 1 remote. Other people prefer to have many disks in a zfs raidz1 or raidz2 array and they run all their apps on one box (truenas, pfsense, plex, video editors, etc.). To me that's too many eggs in one basket.
The fun thing about Proxmox is that a fresh install only takes minutes. So plan on installing it and breaking it a few times until you get it just the way you like. That's half the fun of having a home lab.