Multiple Custom Login UI

We are building an application wherein Users complete a paid form. Before the User has access to the form, they have the option to:

A. Log in
B. Register
C. Continue

If they select “Continue” they will be able to complete the form. Once they finalize the form and are ready to checkout, we need to direct them to Log in or Register before getting access to the Order screen.

Is it possible to have a custom login page for this? The UI would need to be a bit different, containing a bit more information than our standard login page.