Embedded databases are ones which run with your application, tightly integrated but don't need a server. (This might not be a correct definition)
Although I believe some E.D's support concurrent users, I would suggest you go with MySQL for 3+ people, but others might disagree.
Moving data from a csv file is the least of your worries though, as It's probably the easiest part.
I wouldn't recommend you use Netbeans GUI designer though, not unless you've learnt the foundation materials for the GUI side, as it can lead to major issues further along.