• We need to learn and understand the key roles of trading before we go into trading
I'm familiar with most of the points you highlighted here but I'm yet to grab this particular one. I mean what do you really refer to as the role of trading? What are they? Or you probably want to say purpose of trading? I need enlightenment on this point if you have the time please.
• The risk in trading can lead you to lose whatever you have
A trader should bless whatever they worship if they only lose what they have and not losing themselves. Trading deals with emotions and if you can't properly manage to control your emotions, you'll not only lose your money but including yourself due to mental unrest.
• Most important, to understand the Risk management
Most importantly indeed! Knowing how to manage risk is very necessary for every trader whether beginner or professional because it serves as the roadmap for your actions regarding your trade. A proper risk management and assessment will definitely help you to minimise your loss.