How to study endgames

I am 2118 fide rated player who has poor endgame knowledge,studied generally middle game ideas and openings.I want to learn endgames which I need to be a Fide Master.Which study plan is best?Karsten Muller trainers,Jeremy Silman's book,Dvoretsky(It's hard and takes long time)etc.?I am a student and has no much time in school term?Thanks for help...

One of the reasons folks like Silman is that his course is broken down into easily digestible chunks.  Yes, it's a huge book but much of it should serve as both review and a way to organize the endgame knowledge you already have.  OTOH I'm from patzerville, so what do I know?  

So you prefer Silman's book due to it's easy to study?

That pretty much sums it up.  He starts with essential knowledge for a relative beginner and then each chapter is geared for a particular class player,  from E class all the way up to expert and finally master.  Obviously much of this you already know or you wouldn't be rated as highly as you are, but it would seem an easy way to find any gaps in your knowledge and correct them.  OTOH one of the wonderful things about this site is all the posts where patzers try to tell good players how to improve.  Guilty as charged. 

To be fair many of us merely repeat what world renowned GMs and coaches say.  If Dvoretsky gives a piece of training advice in his books then it's a good policy to listen.  He patched up Dolmatov and other players' weaknesses quite nicely, but the students played their parts.  

Basic Chess Endings by Fine/Benko is said to be the de facto reference on the endgame, eg Korchnoj points his readers at that book in his own book Practical Rook Endings. I also like Chess Endgame Training by Rosen, because of its format. every chapter first has some explanations and examples and then diagrams to solve by the reader. But my first book about the endgame was a book by Averbakh, i dont know the name any more, sorry. It also contained tests.

The Endgame Books by Dvoretzky, Nunn and Müller are also said to be excellent.

I bought Basic Chess Endings way back in 2003, the text on the back spoke of it being the definitive and important work on the endgame, implying that to be a real chess player you need to work through the whole thing (I did 2 and a half times) Guess what work that replaced it as the best endgame book came out in 2003?  

Dvoretsky's Endgame Manual is simply better than the competition.  I can imagine how it came to being.  Dvoretsky was training some pupils with it, since Botvinnik carried it everywhere, and had an epiphany that he could do much better.  I have both and they have different positions but even the Benko version has some mistakes. 

This is Die Endspiel Universität in German. It has had many good reviews.