If you want to display any Form without Login (Before Login page), you must select the Page Access as “Before Login” while creating or by editing the Page builder record.
For that, you need to select a Form that is created to display the Before Login page. Add the ‘Form’ widget to the page layout and configure the Form details.
Once the ‘Form’ widget is configured to display without login (before login), the portal users can access that Form without login from the customer portal.
You can preview the Before login Form view.