How Do I Install Linux for a Dual-Boot Setup on a Second Drive?

A safe general order is: make a current backup, create a Windows recovery or installation USB, install or keep Windows first, shrink its partition if necessary, and then install Linux into the unallocated space or onto the empty second drive. You do not necessarily need to manually wipe every partition beforehand—the Linux installer can usually format the selected target—but choosing the wrong disk can destroy data, so double-check the drive and partition sizes.

Linux does not use Windows drive letters like C: and D:. Check Disk Management in Windows, or inspect the disks from the Linux installer, to identify the actual drive and its size. Linux can be installed either in unallocated space on the same disk as Windows or on a separate disk. If using the same disk, shrink the Windows partition from Disk Management first, then select the resulting unallocated space during the Linux installation.

If you want a clearer view of the disks and partitions, a bootable partitioning tool such as GParted can show whether you have two drives or one drive split into multiple partitions. It is useful for inspecting the layout, but be cautious with any operation that deletes or reformats partitions.

First confirm whether D: is actually a second physical drive. Windows assigns letters to partitions, so D: might just be another partition on the same disk. If it is a separate drive and you choose it as the Linux target, the installer will normally create the required Linux partitions there, but you should assume its existing contents will be erased. Back up anything important first. Windows can remain on the first drive, and the boot menu should let you choose Windows or Linux at startup.