Which model of the MacBook Pro is it? If you do not know, then you can use this page to find a way to identify it:https://support.apple.com/en-us/HT201300
The reason that I ask is that it may impact what your options are.
If it is a model that came with Mac OS 10.6 (aka Snow Leopard), but was later upgrade to Mountain Lion (aka 10.8.x), then you will need an AppleID that was associated with a purchase of Mountain Lion to be able to re-install Mountain Lion as I understand it. The only possible exception to this was if that MacBook Pro was one of the ones that received a firmware update that allow it to use the Internet Recovery option...if so, then see the next paragraph...but I am not 100% sure if this true. Otherwise, you would need to use the recovery media (either a optical disc or USB drive depending on model) that originally shipped with the MacBook Pro to restore it to Mac OS X 10.6.x (aka Snow Leopard). The other option is to get your hands on another Mac, create an AppleID to use and then buy Mountain Lion (aka 10.8.x) [or maybe a later version] to be able use that AppleID to re-install Mountain Lion.
If it was a model that came with Lion (aka 10.7.x) or Mountain Lion (aka 10.8.x) installed, then it came with the Internet Recovery option built-in. If so, then the suggestion that dante12 offered should help. As I understand it, with the advent of Apple getting cheap/lazy and not providing physical recovery media with new Macs, the Internet Recovery was meant to take the place of that physical media. So, as I understand it, a new Mac will have the current Mac OS at its time of release set as its "default" recovery OS that is used with the Internet Recovery media...presumably without needing an AppleID. Since I have not had the need to employ the Internet Recovery option, I don't know if this true firsthand. And I definitely do not know what happens with Macs that shipped with 10.6 physical recovery media, but received a firmware update to allow the use of the Internet Recovery option.
As to creating on a Windows PC a bootable USB drive for installing the Mac OS, I don't believe that is possible. You would need something to be able to format in the Mac OS disk format (which Windows does not do) and then be able to write a DMG to that Mac formatted USB drive. MacDrive could do the former, but I am not aware of any utility that would do the later. Does not mean it is possible...rather I am just not aware of a way to do it.