Creating a new database and new connection in Oracle SQL Developer

Question

I've introduced SQL Developer to my framework. No associations are being displayed in my framework yet. How would I make another association? Must I make a data set first? On the off chance that indeed, how would I make another data set? The SQL Query Editor window isn't opening since there is no association. This is since there is no information base. How would I make an unfilled data set and afterward associate with it?