It isn’t nearly as much fun a building a dedicated server, (or what I like to do – repurpose old junk) but the services you mentioned will run just fine on a decent desktop or laptop, especially if you aren’t doing some hungry task while they are running. -1 for Plex. +1 for Jellyfin. You can run them all on your LAN and access them around the house by the machine’s LAN IP and the services’ port number. You can do the same thing if you have tailscale on your phone or other remote computer, just use the tailscale IP and the service’s port. You can use Nginx Proxy Manager to send your services through a cloudflared tunnel to a hostname you buy, and keep access limited to just yourself and a select few (FYI I hear Cloudflared doesn’t like a lot of video streaming, so don’t give access to too many folks).

Jellyfin will run on a windows machine without screwing with docker, and will host your music too, though the UI isn’t great.

You can use a simple fileserver on windows to host other stuff like pics.

Just start somewhere and you’ll be neck-deep before you know it. You can use