reinstall Windows 8 but don't know embedded key

[tmy]

Hi everyone,
got a tricky one here :

The hard drive failed in a HP laptop and I need to install a new hard drive but two problems

One

After starting Windows set up windows 8 error pops

Load driver.

A media driver your computer needs is missing. This could be a DVD, USB or hard disk driver. If you a CD, DVD, or USB flash drive with the driver on it, please insert it now.

Note; If the installation media for Windows is in the DVD drive or on a USB drive, you can safely remove it for this step


I have no clue what it's asking for so I can't continue

Two

How can I know the product key if it's embedded in bios and also in bios I know the OS is Windows 8 I have tried to install but not got past the first error above

I did attempt to use Windows 8.1 to install as that doesn't kick up the first error, however it gets stuck asking for the key ?


Product is:

HP laptop Envy m6 Notebook PC
Model: m6-1206TX
Product D5F63PA#ABG

your help and guidance would be great I don't have a backup or rescue or restore DVD's

many thanks

tmy