The title says it all.
How do you make them Produce Interceptors? I don't want to make them automaticly

set a trigger with certain conditions and when those conditions are met, modify the unit hangar count of the carrier to add a number to that carrier.

If you want carriers to build them, you can also just click the interceptor button. If you want computers to "build" interceptors, then either use a trigger with certain conditions or run an AI script and they should build their own.

To get computers to build interceptors on their own enable the unit and run a Protoss melee AI. Low build time and mineral cost help to produce them faster, but it's still not perfectly reliable.