Are there any guide that I can follow on the programming of scripts??
Here are a few resources that might help you learn more about Lumerical’s scripting language:
Script function tutorial - Provides information on simple task
Script function chapter of Knowledge Base - Definition of each command
Beyond these resources, I find that the best way to learn the scripting language is to find an existing example that is similar to what you want, then to start making your own modifications. I find that modifying existing code is a lot easier than writing everything from scratch. In addition to the application examples in the Knowledge base, the objects in the Object Library (in FDTD & MODE) are another good place to find example code to start experimenting with.