1) Firstly, you will need to purchase a Windows 10 license. This can be done through the Microsoft Store, or from a third-party retailer.
2) Once you have your license, you will need to download the Windows 10 installation files. These can be found on the Microsoft website.
3) Once the files have downloaded, you will need to create a bootable USB drive or DVD. This can be done using the Windows 10 Media Creation Tool.
4) Once you have created your bootable media, you will need to boot from it. To do this, you will need to change the boot order in your BIOS or UEFI settings.
5) Once your computer has booted from the bootable media, you will be presented with the Windows 10 setup screen. From here, you will need to follow the on-screen instructions to complete the installation.
6) Once the installation is complete, you will be prompted to enter your product key. This is the key that you purchased in step 1.
7) Once your product key has been entered, your copy of Windows 10 will be activated.