Well, that's going to be an issue.
One of the first lessons is that while there are a million wrong ways to grow, there are also many right ways, too. Just looking around this site you will see many growing methods and mediums and new things being developed as we speak.
My advice is learn the plant first. Start simple, make a plan, and stick with it through a grow. Make sure you have your PH and PPM in range. Take notes, watch what your plants do in response to their environment and to nutrients. Learn to read the plants.
Once you feel you have a handle on that, then
is when you start developing your own style.
A second lesson is to verify everything you are told. There is a lot of misinformation and myths out there, some perpetuated by well-intentioned people.
Experiment. Make hypotheses and test them. Realize that every thing that doesn't work out is not failure, but a gain in knowledge.
Best of fortune on your journey.