Lan,
There are proper cooking methods, and then there are are "other" cooking methods which are popular with regular, stay-at-home-cook types.
You should research and read on all the available Culinary Topics, as it will help guide you in your journey. Your research will help you decide whom to listen to, versus who is just a home cook with ideas.
If you are serious in wanting to learn how to cook, there are many, many avenues.
Holly
