What is a convenient online event management system?

Question

Work organization

In general, the essence is this:
I am the coordinator of one news agency. My responsibilities include:
1. Search for events/themes/newsbreaks
2. Accreditation for events
The agency is new, actively developing, and therefore has no developments in this area.
At the moment, I use a daily updated .doc file to present to the manager, in which the events are entered in the following

form
: labels, etc.
2. The leader is very busy, as a result of which he often forgets to indicate which events are important.
What would you like:
System with separate access (Administrator - adding/editing events, regular user - viewing only)
Two calendars - as soon as an event is marked as "Required" - it is automatically transferred to the second calendar.