Welcome to Thunkable!
I’m going to move your post over to Thunkable Discuss, since I’m assuming you intend to write your app in Thunkable X, the current version of Thunkable, not the retired Thunkable Classic.
I don’t do students’ homework in response to posted specifications. If you’re stuck, please post what you’ve tried so far (block screenshots are always a good idea) and a specific question you need help with.
There’s pretty good documentation on doing sign-ups with Firebase. That might be a good place to start: Email Sign In by Firebase - Thunkable Docs or Email Sign In by Firebase - Thunkable Docs depending on which version of the interfact you’re using.
There’s also a great tutorial, sample code, and discussion here: Sign In Masterpost - #2 by jane