What is this best method to cultiva-te and extraction of cannabis ?

The answer to such an especially broad question would absolutely depend on your location and your end user's expecations and preferences.  Indoor cultivation can be cost-prohibitive for smaller operations yet necessary because of your climate, but will give you the most consistent product and annual biomass yield.  Depending on your goals with the end product converning extraction, all methods have their pros and cons with solventless options having the lowest barrier to entry.