How long before webinar features available?

Welcome to the Zoom Community, @chassidy.

You need to assign your newly purchased Webinar license to your user account. See this web page for assistance:

https://support.zoom.us/hc/en-us/articles/115004976063-Assigning-a-License

Follow these steps taken from the article:

1. Sign in to the Zoom web portal at https://zoom.us.
2. Click User Management, then Users.
3. Locate or search for the user who you want to assign a license. There will likely only be your single account – click your account
4. Click Edit at the end of the user row. This will open a window.
5. You likely have already assigned yourself the Pro license, but if not, select Licensed to assign it to you.
6. You should have a Webinar license available to assign. Check the box for the available license to be assigned to you.
7. Click Save.

The license is now applied to your user account and you can use it immediately.  On your Zoom Web Portal "Profile" view (https://zoom.us/profile), you should see all licenses assigned to you; look for the grey bar that says "Account":

Yours will look a little different than mine, I'm sure.  But it should say "Licensed" and include the "Zoom Webinar 500 attendees" items.

If this does not fix your issue, please submit a support ticket to our Billing team here and they should be able to assist you.

https://support.zoom.us/hc/en-us/requests/new?ticket_form_id=360000983032