The PowerSchool Community is a great resource if you have any difficulties completing fields within the enrollment form. Each district, however, has a different process for student registration and can provide the best steps to move forward when enrolling students.
If you have not received the link to your registration form from the district or it is not available for you in the Enrollment, you would need to directly reach out to the district and ask them to send you the link. You can also access your enrollment forms through the Parent Portal by following the steps mentioned in this article: Accessing the Form using PowerSchool Parent Portal.
You can check out the FAQs related to the enrollment process here.