Trading is not so difficult as it was told. But the difficult part in trading is when to enter the market and when to Close the market. So when do you think one can buy or sell (enter) the market? Using the candle sticks to predict.
it's always on the candles stick where you can get an idea when to sell and to buy in a particular level in the market base on its structure and movement and that is called price action.
And yes that's the most important strategy when it comes trading because everything will become so easy to understand and to predict even there's no clear trend in the graph.
By being able to read candles, we can read price action so from there we can determine when to close or open a transaction. actually it is not that easy to determine when to enter and exit the market, because not all candles are like our theory. on the other hand we can use EMA to determine price action, the smaller the time frame we choose, the smaller the candle space will be