Because you have had this laptop for some time and you are lacking in some basic computer knowledge I can only suggest that you take it in somewhere to get it fixed. Anything we suggest will be beyond your level.
If on the other hand you are only pretending might I suggest that you first double check the hard drive connections (power data) as one may be loose. This requires the knowledge to locate the HDD in the laptop. Even try swapping out cables to verify the problem is more than just power or data communication to the HDD. Thus the suggestion of taking it in for repair.
Keep in mind that by taking it somewhere you very well might loose your personal data stored on the HDD. But this is a moot point if the drive has physically failed (and not just a connection) as a failed HDD is unaccessible.
Unfamiliar terminology definitions can be located on the internet via Google or similar sources.