I want to keep all my working files in a separate tabs in Brackets since, I am finding bit difficult to open the file in the LHS panel under "Working Files". Is there a way to do it?
The Tabs for Brackets extension will show traditional tabs along the top, although only when the sidebar is hidden. (Though it would probably be easy to hack that extension to do it all the time instead).
But bear in mind that the "working files" section is really the same thing as tabs, just rendered in a vertical stack on the side to conserve screen real estate. You can open, close, and drag to reorder the items just like tabs. If clicking them is a pain, you can use Ctrl+Tab to navigate in MRU order, or use my File Navigation Shortcuts extension for hotkeys to navigate in linear list order (or use Quick Open to jump to any file based on a fragment of its name).