Yes, you can do this.
Yes, you can do this.
You're upgrading your motherboard and CPU, and you're trying to run Windows on a different hard drive. Since you have an OEM setup with two drives—one already containing Windows—installing Windows on the other drive should work as long as the drives are compatible and there are enough free space. You can delete the existing Windows installation if needed before proceeding. Just ensure the new installation has sufficient storage and meets system requirements.
Adjust your boot sequence and format the existing OS drive accordingly.
Make sure to disconnect the hard drive before installing Windows, as the installer can cause unexpected issues and inserts data onto the second drive.
You can reinstall them, obtain Steam, clone the applications using Clonezilla, or start from another hard drive if you don’t erase it by booting from that source.