Normal work flow in texworks
Normal work flow in texworks (and in any other text editor when your are editting latex file):
1. Open with texworks desired file or make new one.
2. Fill your document (with LaTeX command, text and etc).
3. Compile your document with pdflatex (Typeset, 'pdflatex', Ctrl-T).
4. If there were no errors another window will pop up and you will see your document.
Details:
1. How to open given file in texworks. Either as you already do, or simply run texworks and use 'Open' in 'File' menu. If you want to make new document run texworks and choose 'New' from 'File' menu (actually when you run texworks a window is opened with empty document).
2. You should know how to write document using LaTeX. There is manual:
3. TeXworks not only helps you to edit your LaTeX documents but also helps to typeset them. Use 'Typeset' menu to choose desired engine or tool (actually they are all tools, they are configurable and you could see what they do in 'Edit' -> 'Preference' -> 'Typeset').
TeXworks could run 'pdflatex' engine on given file if you press Ctrl-T or press button on toolbar.
4. If there are errors in document compilation the error message box will appear at bottom of editor window showing relevant information (as it would be shown in terminal window).
Don't forget that texworks is an editor.