Meetup Group URL: You need a meetup group URL. So you have to go meetup.com and copy your group name from the URL. Example:
http://www.meetup.com/your-group/

Import type: If you choose one-time-Import it will import only one time.

Import Type: If you choose scheduled import it will give you option once Daily means event import once in a day, once Hourly means one event import hourly, Twice daily means two event import daily, Once month means one event import monthly.

Import into: If you choose WP Event Aggregator your event import into WP events.

Event Categories for Event Import: This option helps you import events and assign them to the chosen categories.

Status: This option allows you to easily import events into the selected event status.

You can see events on WP events .so this way you import your Meetup event using  Meetup Group URL.