OK, see if this works...I'll give you the instructions for both W8 and W8 Pro...
Install W8.1 by creating the Microsoft installation media, using another Windows PC, if yours is not working...You want W8.1 64 bit.
https://www.microsoft.com/en-us/software-download/windows8ISO
If you are asked to enter a product key during the installation process, use this generic key.
This is the generic key for W8.1 'Standard.'
334NH-RXG76-64THK-C7CKG-D3VPT
If you had to enter the generic key, manually change the generic product key to the W8 key in your PC's BIOS in the PC settings menu.
After you get W8.1 installed, and you had to manually enter the W8.1 generic product key, you will need to run the free utility I zipped up and attached below, that will show you show the W8 product key in your PC's BIOS.
I have also zipped up and attached below, the Microsoft tool which hopefully will transfer the ISO file to a DVD or USB flash drive so it is bootable.
Then you can install the available drivers and software from your PC's support page.
https://support.hp.com/us-en/drivers/selfservice/hp-probook-470-g1-notebook-pc/5405414
Now, if the showkey plus utility indicates that your PC came with W8 Pro, go back and download the W8 Pro 64 bit ISO file and use this generic key instead if you are asked to enter a product key...
XHQ8N-C3MCJ-RQXB6-WCHYG-C9WKB