i have an acer pc with dual core pentium processor with american megatrends bios but after entering the bios it doesn't contain any option for overclocking.... So i need help cause i want to overclock my pc
That is a possibility. Without more direct interaction I don't think this can go any further. You say you can't see certain things, but you aren't saying what it is you are seeing.
At this point I suggest researching the topic yourself.