Help...Upgraded hard drive but Lightroom catalog is on old hard drive

I'm using Lightroom Classic on Windows 11.

I upgraded my hard drive but didn't think about needing to backup my Lightroom catalogs. I have over 20k photos cataloged on my old hard drive.

How can I access my old hard drive now, without harming it, so I can open Lightroom and backup the catalogs?
My hard drive is a NVMe M.2 and I have a USB enclosure that I can plug the drive externally into my computer.