Hi David,
Thanks so much for reaching out and for your interest in our products!
If users have Admin credentials, then they can add events from the backend of your site.
You may also be interested in reading more about Roles and Permissions:
https://theeventscalendar.com/knowledgebase/admin-roles-and-permissions/
Also, with Community Events, users can add events from the front-end of your site. You can choose whether to have these events published right away or saved as drafts, so that you can review them before publishing.
Let me know if you have any other questions!
Thanks,
Jaime