How are Cloudflare tunnels different from a VPN?
Both let you access your services remotely but they do it in very different ways.

Once you've got the home lab bug and have several self-hosted services running, especially those that you might want access to at all times, like an image library, you'll want a way to access those services when not on your home network. While there are any number of ways to do this, they all vary from very easy to much more involved.