That all depends on your motherboard. Some mobos have the capability, some dont.
Theres Motherboard Monitor by livewire that can be found here
. Youll need to know the make and model of your motherboard to properly set it up. But theres a chance your mobo simply doesnt read ambient temps.
guess123, to enter your BIOS press delete (or possibly F8) at your boot screen. But if you dont know what youre doing I really dont recommend poking around in there. Change nothing and be sure when you exit you choose to exit without saving changes.