Hey! Welcome to the fold 
If you have a standard deadbolt in your front door, I recommend getting the xNT and a Samsung Ezon door lock. They work great together and the Ezon leaves no extra holes to drill in your door… just replace a standard deadbolt lock cylinder and you’re up and running in no time!
As for the difference between RFID and NFC, read this FAQ (and all the other entries in the FAQ section!)
With the Samsung Ezon lock, you don’t program the xNT chip, you program the lock with the xNT’s serial number (UID - read this).