If you have been assigned as a host to a shared event type and want to remove yourself, you can do so by following this procedure:
On your Home page, find the shared event type you want to edit.
Select the shared event type tile.
Select Remove me at the top of the page.
If you are not an owner or an admin, removing yourself from a shared event type revokes your access to modify and edit the event type. All events scheduled prior to you removing yourself from a shared event type will not be affected.
To remove yourself from shared events that have already been scheduled, you will have to remove yourself from the calendar event or cancel the event.
How to edit hosts for shared events
How to set up a collective shared event
How to set up a round robin shared event