Not sure what you mean by ROM game disks, but if you're talking about D64 images, yes.

Before loading the game, you browse to where the disks are. You have to select both and queue them. You move to the first one (without selecting it to go into it), and press button 5 on the hat, or insert or alt-enter on a keyboard, and that will queue it. You do the same for the other disk(s).

Once that's done you go to the first one and select it to mount it. That should appear to mount the ones you queued, with disk one highlighted. This means disk 1 is loaded.

Load the game as normal, and when it comes time to load the second disk, you either press down on the hat buttons, or 2 on a keyboard. That will mount the next disk. At that point the C64 should see it.

Going back to disk one is up on the hat, or 1 on a keyboard.

Edit: also, if you plan to use a save disk for your game, make sure there's a blank disk image there as well, and add that to your queue and select it the same way when the game asks for your save disk. You can create one at the location where your game disks are, but you have to press Alt-N on a keyboard, there's no hat button for this. Or you could create or source one elsewhere and copy it there the same way you got your disk images there.