Find a project and build a home lab. Build it the hard way, maintain it and open services to your family.
Same ideas: ebook library like Kavita, or Plex server, or Ad Guard, or VPN for the times you’re travelling, or NextCloud for your personal cloud drive, or folding@home if you’re feeling charitable with your compute power.
Anything, the important thing is to get started. Each project has different routes of installation, depending on what you wanna learn, make it happen through research and learning.