Will Programming Fob work Locks & Immobiliser?

Hi, when programming the key as per the instructions on Programyourkeys.com, will this also program the transponder to work with the car as well or does it onlcy program the locks. Bit vague on website.

If only lock/unlock, how can I get the new fob's transponder to work with the car's ECU.

I only have one key and need a spare. Thanks