Hey Debra,
Thanks for reaching out.
To be clear, our plugins are not standalone pieces of software. They are WordPress plugins.
So, you mention having one site.
Install The Events Calendar and Events Calendar Pro on this one site.
Then, you and your team can all log into WordPress site’s wp-admin. You can share one account, or have several administrator accounts.
Then you can all create and update/edit events on the site whenever you want from wherever you want.
I hope this information helps!
George