Did you mean "Drive" and not "Card".
If so then, as mentioned, simply dragging the folders over to the other drive would work and Lightroom would recognize it just like the original drive as long as the other drive had the exact same name.
I don't do this as my drives have different names to avoid confusion (i.e. like "Photos Drive 1" for one and "Photos Drive 2" for the other).
I use SuperDuper cloning/backup software to make the content of Drive 2 the same as Drive 1(there are other programs that do the same). The drives will still have different names.
I would then basically only use Drive 1 in Lightroom but know I have an exact copy on Drive 2.
If Drive 1 was broken for some reason I could use Drive 2 in Lightroom either by changing its name to Drive 1 (easiest way) or remapping it in Lightroom. To remap when the back-up drive is used, the Lightroom file structure will have a bunch of question marks for the folders it cannot find, right click on the highest level folder(s) with a question mark to get to the "Find Missing Folder"command and then navigate to that folder on Drive 2.
Your Lightroom catalog files (which normally do not have your original photo files - they are on your Samsung drive) will likely be in your"Pictures" folder on your MacBook. Cloning Drive 1 to Drive 2 will not back-up the Catalog files but a general backup of your MacBook will or if desired you can manually copy the catalog files to the back-up drive after making the exact copy/clone.
I prefer the cloning strategy for the original images as the files/file structure are exactly the same on both drives and after the initial back-up all subsequent back-ups are fast. My Lightroom catalog files are then backed up when my computers drive is backed up.
There are other ways of achieving what I think you want but I find the cloning method the easiest.