There are 2 ways to do this...
1 - You could use the Fablink tools to create your own panel with the multi-up array.
2 - You can use copy circuit, but the circuit would also need to be duplicated in your schematic.
But here is the correct method...
All pcb designs are typically one up data sent to the fab house. Once there the fab house will do the multi up array on the panel size of their choice. You need to do nothing. Just tell them that you want to order a Min Lot fabrication. Then the fab house will put as many of your boards on the smallest panel they use, as they can. They will fill the area for you.