What is the best language to hack in, and can somebody make a good course in hacking because I want a career in cybersecurity
Hackers don't often use code (unless they're sending out a virus). Instead, hackers figure out exactly what your code is doing in the background and figure out a way to bypass that. Let's say someone named Alice had a contact form:
Alice's form uses a post request to send the info to the server.
She made a design mistake, though: validation. Anyone can type ANYTHING into the fields.
OK, so say someone named Bob went to the website Alice's form is on. He cracks open the element inspector and sees NO VALIDATION in the sending of the form. Bob starts to think about how to hurt the server with this. His choice is to write a program that generates spam above the buffer size in order to exceed the bandwidth. Bob sends it, and Alice's mistake is proven costly to the website, since she also didn't have any backup.
Disclaimer: none of what Bob did is recommended, as it is evil and illegal. You probably already know that, though.