can i improve my rating to 1000 with this book?
Is Silman's Complete Endgame Course a best book for those who know basics?

ok but i am in a dilemma now.please see some of my games and tell which phase shall i concentrate and the book of that phase

You cannot go wrong buying Silman's book. At a low rating of 546, you of course need to play a lot of slow games--I prefer daily games at 3 days per move--and really think about what you're doing. Look for hanging pieces, one and two move combinations, etc.
Also lots of You Tube videos such as agadmator's channel and Mato Jelic's channel, and playing over master games here on chess.com.
But, back to Silman's book. It is, I believe, a timeless classic. Study of this book, especially the first two sections, will open your eyes to dozens of ideas you had never considered, and will improve your play in all areas. Though you may only be ready for the first chapter now, it's never going to be outdated, and you'll find yourself returning to it again and again.
I agree. You will not go wrong with Silman. It is a very readable, motivating book, which you will also be able to use later... At your level though you don't really need to read a book: play slower games, practice tactics, learn from youtube videos... If you want a book you probably want to grab a beginner's book that covers all areas a bit... Capablanca's book is good as far as I remember... there might be better books for beginner's though.
then which book shall i buy as mentioned earlier my rating in blitz is 547
You will benefit more from this book.