As Jet Stream said, you can't count foreign theory exams for the FAA written. If you hold a foreign commercial license with an IR or a foreign ATP you will have to have your CAA verify your license to the FAA, complete an ATP Certificate Training Program, pass the ATP written and pass a checkride. If you are doing the ride in a light twin you will also need at least a FAA third class medical. If you are doing the ATP ride as part of a type rating you will need to complete a part 142 training program but you won't need the medical.