Windows 10 free download (1 Viewer)

Where did you get it from? Ususally they will be OEM so you have to get a rescue disk from them.

You could take it to a dodgy laptop place to re-install it or fix the install.

Dare say you've got this sorted by now LG but if not, you can download and run the creation tool from Microsoft, which will give you an ISO file you then burn onto a disk. Running this should give you the option to "repair" Windows.
Windows 10

If you need to do a complete fresh install, use the same disc...I think you've got about a week before you HAVE to put in a licence key. If you haven't got a label on your laptop with the licence key, you'll need to get one. You can search the net for some dodgy free ones, but if you want it all nice and leagal, and be able to do updates without having to keep finding hacks, there's a few places on the net where you can buy cheap, legal keys. I got mine from here last year, only about £20 at the time, saved a lot of fannying around.
G2PLAY.NET - BE SMART, PAY LESS ;)