I was unaware that scholar press have a bad reputation. I wanted to gain the copyright as I was afraid it will be misused. So I published it as book. Now I came to know they are not genuine publishers. But for visibility it worked. But if I want to publish in some reputed journals what shall I do? Shall I cite the thesis and the book? If so can anyone please help me with format and ideas.
In general you should always cite work you have previously done when you use it. If you don't, you open yourself to a charge of self-plagiarism.
The reason for citation is that a reader may need to go back to earlier work to get a full picture. The earlier work included context that is likely missing in the current work, such as the references you used, etc. And a citation should be to something that is available. If the thesis isn't available directly, then cite the book.
But don't let one bad choice lead you to make others. So, yes, publish your papers, and cite your earlier work as needed.