Anyone with any idea or any handbook or something like that which can help me to understand and allow me to get ahead with this topic of NetSuite scripting?

Thankyou so much for your response Watz.👍

That book is an excellent resource for someone with development experience, not so much for someone with no experience. You really need a good grounding in development principles and a reasonable grasp of JavaScript, heck, any OOP or scripting language really. Just don't dive in to SuiteScript you're likely to introduce all sorts of horrors in to an account.

Thanks a ton.