in laptops, F1 and sometimes ESC key (Depends On manufacturer) is used to opn BIOS controls, DEL on Desktops, f10/f11 on Intel otheboards and so on.
so as u said, that BIOS should open on startup-, isnt applicable, as this key would be someother than the one used to open BIOS controls.
now as far as this problem is concerned, have u ever got soem liquid split on ur keyboard? sa it happens tht keyboard circuitry works as in case a key is pressed, the circuit completes. and sent to system, so there might be a possibility that something might have got stucked between key board circuitry and keys,, and therefore though key shows that its not pressed but actually completing the circuit, that might be some of non writing keys, like ALT, CONTROL, F's, HOME) as if it has to be some alphabetic, then it should have started writing the moment u opeended some word program
download some key checker program, and see what key is being pressed.
and as well, blow hard on ur keys, may eb that thing gets out.
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