How to implement user's public and private data in gun?

I want to have users to maintain public and private data, in a manner that private data is encrypted and public data is readable (but not writeable) to all other users.

In documentation, there's a way to get user public data:

gun.user(publicKey).once(console.log)

However I didn't understand where/how to put user data and how to make it public (for all) or private.

from How to implement user's public and private data in gun?