A limit order (sell) means to be executed if the price touches the order price not above prices, I am correct? Example:
If the market price is 3.74 and I set a sell order on 3.56, the price should be executed on 3.56 (if the volatility and amount of orders on that price makes it possible), not on the MARKET PRICE because the system found a better price and decided to sell.
No, that's not accurate. If you place a limit sell order at 3.56 while the current market price is at 3.74, the order will be executed immediately at the current market price (3.74).
What you're describing is a stop-limit order, which means that the system will only place the limit sell order once the market price reaches 3.56.