How do I create a signup screen?

How do I do X?
1

I want to create a public app, so the users will sign up by themselves.
So I want a screen where they enter either their email or google credentials plus a username.
The process I have in mind is similar to the one used by this knowledge base to signup the users.

I just can’t find any related topics in the documentation.

2

@CultureCitizen you can create a form login following this guide