4 layer PCBs with Fritzing
If you want to make 4 layer boards, use a real tool, not a toy. Design Spark PCB is easy to learn. KICAD is a bit more difficult. Both are free, and support unlimited layers and pins.

As has already been said PCBs come in lots of layer counts. The same can be said for soldermask color, material, thickness, copper weight, and finish.