Had no idea what Paper Toss Game was until a few moments ago. Apparently I'm pretty bad at it...
It is a 3d game so it's harder to do as it will require math to pull off, not impossible but certainly not the best candidate for a first game especially since C2 is geared for 2d games.
First see if you can make the game in only 2d as a side view and then a top view. The bullet behavior can be used in both cases. For the 3rd dimension you'll need to use a variable to keep track of and adjust the Z position or distance into the screen and change the paper wad's scale based on that. There is a tutorial on psuedo 3d that may help with some of the math as well.