Your files would remain on your HDD even after reinstalling Windows on your SSD.
Your files would remain on your HDD even after reinstalling Windows on your SSD.
Make sure you choose the right driver for installing Windows, and avoid formatting the second option. Then everything should appear once the installation completes.
It should be okay. Just confirm you install on the right disk to prevent any awkward issues. Disconnect the HDD while this happens. Remember, back in the day Windows could run its main setup on one drive and load the MBR onto another without much trouble—just avoid the disconnect unless necessary.