If the laptop actually do not have a hard drive or it is dead, then you need to install a new hard drive. Then at that point you can install Windows. If you already have a Windows install disk, then just put the DVD into the DVD drive. If you do not have any Windows OS install disk, then you need to buy one. Lastly, if your laptop does not have a DVD drive, then you need to buy an external DVD drive so that you can install Windows.