Did you not remove the old pressure plate from the flywheel yet? You re-use the old bolts if there's no damage to them. The flywheel is attached to the engine crankshaft with bolts of it's own, normally these aren't removed unless you are getting the flywheel resurfaced or doing a rear main engine seal or something. Be sure to note correct installation of the clutch disc too as it came out when you remove the pressure plate, whether the protruding side of the disc goes towards the flywheel or the pressure plate, it varies on some designs.