How to download windows 10:
After downloading the file burn the file in to the cd.
Now, place the cd in external cd writer and connect to the computer which you want to install.
After connecting select the boot option my system boot option is F12.
Next press enter.
[shift+F10 to open command prompt while installing os and we can create new partitions.
Delete all old partitions and click on new to create new one].
Installing windows 10: