After the opening

After I play my opening and start developing the pieces, I always get stuck choosing what to do next, I don't find any good move to do, so I start trading the pieces. Is it a good idea? Any suggestions?

Between the opening and the endgame God created the middle game. 

Whether or not to trade pieces depends on the position and what you are getting out of the trade. Try playing through Logical Chess by Chernev. It is a collection of GM games selected and annotated to teach basic principles to beginners. Amazon have it. Look for the modern algebraic edition if you can find it. Play through each game a few times, maybe one a week, and make some notes about what is going on in the middlegame and things you should start/stop/keep doing in your own games.

Okay, I will follow what you said, thanks!

Not a good idea. Suggestions... look through complete games that are annotated. I'd recommend logical chess by chernev. 

Alternatively, you can buy an opening book that has complete games of the opening you play. That way you get to see common plans, themes, tactics, maneuvers, piece placement, etc.

     Play longer time controls. You need to take the time to think about the position. Learning positional principles from the Chernev book or the writings of Tarrasch, Reti, Nimzovich and many more or the lessons and videos here on chess.com is the next step, but you need to take a few minutes to analyze the position. Look for potential weak spots in your opponent's position and figure out how to take advantage of them. See if you can think of a way to create a weakness in your opponent's position. Think of what your opponent might do to weaken your position and look for a way to thwart them. The key is to come up with a plan--he has a backward or isolated pawn I can pressure or put a piece on the square in front of, he has weakened his king position so I should build up an attack, he has a queenside pawn majority so I better put some obstacles in his way so he can't exploit it, etc. You need a long-range strategy to help you figure out what immediate tactical will yield the best positional results. "A bad plan is better than no plan" as Tartakower said. So learn what positional play means and put it into practice.

@B1ZMARK great advice! 😁

Great suggestions, I will for sure implement them in my games, thank you guys! (I am buying that book right now!!)

Hi! My name is Lauren Goodkind and I’m a chess coach based and chess book author based in California: www.ChessByLauren.com

Trading pieces is okay, but always have a plan too.  Ask the question, "If I trade, how does this benefit me?"  

Before every move, ask, "Is there a way where I can force a winning line so I can win material?"

   To help you, consider all checks and captures.  

   I hope that this helps.