As Zayev said you can buy a USB drive to do it with. Another option you might be able to do is to take it into a PC shop near you and have them install it for you then use your key.

Majority of the time they'll have disks/usbs around with all kinds of OS on it for troubleshooting and repair purposes although they might charge for it.

I have usbs, just not with os's in them. Thats the problem. I cant download anything or use ie because i have no os. I think ill just buy a disc or something. Thanks for your help

TRAW wrote I have usbs, just not with os's in them. Thats the problem. I cant download anything or use ie because i have no os. I think ill just buy a disc or something. Thanks for your help

If you have a 4GB USB then take it to a friend or family members house or even an internet cafe if they allow downloading (unlikely but it's possible) and download the ISO. Use that ISO to create the bootable USB for your PC.

Do you not have a laptop or something, or even a phone that can be used to download the ISO

Zayev wrote Do you not have a laptop or something, or even a phone that can be used to download the ISO

Can you make a bootable USB by mounting ISO off a phone?

if it is a rooted android device then you can

I have an iphone. The laptop is broken so thats off the table

I believe microsoft offers a windows 10 download for free, so if you have an extra laptop, set up an installation drive using the download from their site. Once that is done, plug it into your PC and when you boot it up, open up the BIOS. Then choose the flash drive as your boot drive. It should then bring up the windows 10 installation screen. At some point along the installation, it will ask you to enter your key!

Good luck:)

Will a samsung galaxy note 4 work?

or you could just buy a disc...