Thewhitepanther :
the company I bought my pc from already oc it would it be best to ask them how they overclocked it
They most likely did the overclock in the BIOS since that is the preferred method. The way you enter BIOS differs depending on which motherboard you have. On my Gigabyte brand motherboard you hit the delete key while the computer is booting up. I usually just keep tapping it rapidly after I push the power button until I see my BIOS menu. If you boot all the way into Windows you either didn't time it right or your motherboard has a different key for entering BIOS.
Once you are in the BIOS you want to look for the CPU core multiplier options. If you are currently overclocked to 4.6Ghz your current multiplier would be 46. You would want to switch this setting to auto. You would also want to set your VCORE to auto since they likely increased that from stock to get a steady overclock. The way this is done varies by motherboard so I can't really get more specific than that.
Before you make these changes though, you never really explained what kind of temperature problems you are experiencing. What are your temperatures under load? You can run a free program called HWInfo to see these numbers. Are you experiencing thermal throttling or crashing while gaming?
We want to be sure you actually have a temperature problem before you remove the overclock, especially if you aren't confident in your ability to remove it.