How Can I clear out People from my registration forms

If what you mean by clearing out people is by deleting submissions, you can delete them by going to your form's submissions page. This guide will show you the steps on how to delete your submissions: https://www.jotform.com/help/377-How-to-Delete-Form-Submission-Data

Please note however that deleting submissions will not free up your submissions limits for the month. The monthly limits will clear or restart itself on every 1st day of every month.

The freeing up of space in order to accept more submissions will only apply for file storage submission limits.

If you have other questions, please let us know.