If the volume of a cylinder is 1.01 L at STP (0 C and 760 Torr). If the piston is depressed 5.62 cm further into the cylinder, by how many times will the gas pressure increase?

What formula would I use to solve this problem? I tried using P1V1 = P2V2, but I don't know how to find V2

Read over the problem carefully. Have you typed all of the information given? For example, do you have a height of the cylinder or a way to calculate it?