In Europe, your ATPL theory exams cover the CPL and the IR. You're issued with a CPL when you pass that flight/skills test. Then you get a job and accrue hours. Once you have 1500 hours (with various break downs of night etc) AND you're flying a CS-25 EASA (similar to the FAR 25), then you do the ATPL skills test during the sim programme. (I think you need to be 21years old before you can do the ATPL skills test)
The US does the PPL - CPL - ATPL theory exams separately. You need to be 23 before you can be issued an ATP licence in the US. I'd spend a bit of time
here