Import By: You have to choose Facebook Event Id from the drop-down for import event by Facebook Event ID.

Facebook Event ID: You want to enter the event id of Facebook events.

Import Into: You can choose Facebook Events (or from where you have to import like an event manager, ) from the drop-down list.

Status: You can select the option of published or draft events.
Then you click on Import events button events import in your WordPress.

Facebook Event ID: You are also going to need to know the Event Id of the event you wish to import – this can be quite easily determined by looking at the URL of the event on facebook.com

Now you see an event you get ID of a particular event on click of that event.

Copy this ID and enter it in the large import events by their Facebook ID field (noting you can actually add lots of different IDs – just place them on separate lines)

Now You can see Imported events on Facebook Events .so this way you import your Facebook event using  Facebook Event ID.