So once I got XAMPP up and running, could I just get the source code of a random page that I know is vulnerable and run for example paros, and I will eventually find whats vulnerable, or have I got this all wrong in theory?
Or do I need to actually set up my own web page for this to work?
If so, I'm sort of lost, as I can't figure out how to actually use paros proberly, I'm not sure how I even run it in a proper way, so I guess I have to do some more reading and testing and see what I can figure out.
This is sort of a side project for now, but I hope I will make some progress sooner or later, because this really makes me get the feeling that I want to learn this, as it's very interesting and I think I will have need for this later in life

Once again, thanks Goatboy for helping me, and answering my questions in such a good way that even I managed to understand it in a proper way, hehe. I hope I soonish can post some progress to show of what I've learned