Move boot from C:\ drive to internal SSD

Hi all,

Luckily I looked into this before hitting to "proceed" button- it seems that my idea of cloning my internal drive to the other internal drive and booting from the newly cloned drive is not possible.

I just want to swap the drives the OS sits on.  Do I need to unplug the c:drive after the clone then start the computer and once it is running from the new disk plug in the c drive and format from there?  Can I plug in the drive to the motherboard when the computer is on?

I'm a little lost.  I just want to use my smaller SSD as the OS and format the C: drive (a larger, faster Pcie ssd) to be empty and start from scratch for video editing purposes.

Even in the case that I used the ssd in an external enclosure for the cloning process (which I can do) wow would I even check if the cloned drive works if I can't boot it when the original c drive is installed?

UPDATE:

Can I copy the C: drive to the external SSD via USB then unplug then boot on original disk then plug in the cloned disk and change the  drive letter of the cloned disk to something else?  Then when I boot in BIOS it woun't be competing C:drives?  Is that the way?

Thanks for the help!