Your account’s Access Control is currently configured to handle log in and registration on your own site. For that to work with the widget, an additional script tag needs to be generated by your server. Consult the API documentation for more information.
This widget only works on modern browsers. If you want to support users with an older browser then you could use an integration via a link instead.
This is what it will look like on your site with the currently selected options:
This page will show examples and code snippets relevant to your account if you log in.