There is a step I think can be optimized, but I don't know how to modify it.

When the customer is not logged in, click checkout on the shopping cart page, and I want to jump directly to the registration page.
I am using the 1.55F version of zencart
One-Page Checkout version 2.1.2
I don't want customers to choose to log in or register when they check out.
Because I found that many customers shut down my website on this page.
They should prefer to see the registration information as they are new customers.

How can I modify the code to implement this idea?