I did not validate my windows 7 microsoft office since i bought my laptop about 6months and now its not recognising my product key under my laptop. how do mi get to use word,excel,powerpint

The product key under your laptop is for your operating system (ex. Windows xp, vista , 7) and not for Microsoft Office. You will need to look on the box of the software for the key to Microsoft Office. If you no longer have to box but you have to receipt you can get in touch with Microsoft to activate the software over the phone