I need to know the type of bolts that secure the

Hi,
It is best to buy a new set of head bolts when doing head work. This is because they stretch when torqued, and may not like doing it again - possibly failing, so for £20 or so - it really isn't worth it.
Use a light smear of anti sieze on the threads and under the heads to avoid tearing.

You are likely to need a medium torque wrench - and also angular tightening information specific to your engine.

Don't forget to re-torque after run-in.