You can start by experimenting on your current computer. Install docker, get some service that sounds interesting, and just access it on localhost. You'll miss out on anything the service does overnight or downtime, and you won't be able to access it from off-site, but it's a fine way to wet your toes and see how it goes.

Docker: https://docs.docker.com/desktop/setup/install/windows-install/

Photo library: https://docs.immich.app/install/docker-compose/

Some maintainers even provide handy windows installers

Media library: https://jellyfin.org/docs/general/installation/windows