The Academy works without an account. Signing in is how your progress follows you to another device.
You never need an account to learn here. An account only carries your progress between devices.
If that address can receive an account here, a confirmation link is on its way. Open it on this device to finish.
This link lets you set a password and nothing else. You are not signed in yet.
Your local progress is never deleted by this step. It is copied up, merged with whatever the server already holds, and kept where it is.