javascript – How to perform a web scraping with WebScraping?

A long time ago, I wanted to learn a lot of subjects. The problem is that the Internet can be all there is, but there is also a lot of unwanted content that can make you waste a lot of time. And what better to ask in this community of experts.
I'm really looking forward to discovering WebScraping (something I know, I want to become an expert like you), my idea is to learn how to do it without using APIs.
-I know that if you make a lot of requests, they forbid you, they detect it through the user agent, how can I do it so that they do not detect me?
-in case of wanting to write. For example, I make a script in python, where I take the facebook page, I want to write something and after its publication, how could I do?
– another question and I take advantage of what I am here, where I can realize a computer security course? I read a lot too, I know that they use Kali Linux and its applications … but I find it odd that a hacker is using something standardized.

thank you so much