Yes two drives is much better than using the same drive to dual boot. However be aware that windows update will at some point break the Linux install even if installed on a second drive. There's a few steps you can take to avoid this like making sure the boot partition and booy manager ate both on the Linux only drive but Microsoft messing something up is an inevitability.

If on a laptop with only one drive, you could boot to a USB drive or USB external enclosure for an SSD.

Ideally, you should back up all data to an external drive which is only plugged in during backups (unplug when installing another os). I would even recommend windows users booting into clonezilla and cloning their windows drive as it is really easy to overwrite or format the wrong drive.